EP4014210B1 - Method and device for examining value documents - Google Patents

Description

The invention relates to a method and a device for checking valuable documents, in particular valuable documents that contain at least one luminescent substance.

In the following, valuable documents are understood to mean sheet-shaped objects that, for example, represent a monetary value or an authorization and therefore should not be able to be produced arbitrarily by unauthorized persons. They therefore have security features that are not easy to manufacture, in particular to copy, the presence of which is an indication of authenticity, i.e. that they were manufactured by an authorized body. Important examples of such documents of value are coupons, vouchers, checks and especially banknotes.

Luminescent substances are often used as a security feature. Luminescent substances are characterized by the fact that they show luminescence when excited with suitable excitation radiation, that is, that they can be excited with excitation radiation in an excitation wavelength specific to the respective luminescent substance and, as a result of the excitation, optical radiation with a spectrum characteristic of the respective luminescent substance, in Also referred to below as luminescent radiation. The spectrum of the luminescent radiation has maxima at one or more wavelengths that differ from that of the excitation radiation. Furthermore, when excited by an excitation radiation pulse, the luminescent radiation is not emitted immediately, but rather over a certain period of time with decreasing intensity, which is referred to as decay behavior. The decay behavior is also specific to the respective luminescent substance. Luminescent substances often give off at a given intensity The excitation radiation emits luminescence radiation with a comparatively low intensity, which makes its measurement significantly more difficult.

Depending on the type of valuable document, luminescent substances can be introduced into a substrate of a respective valuable document of this valuable document type as a security feature and/or applied, for example printed, to a surface of the substrate. The authenticity of a document of value can then be proven by testing the luminescence behavior, for example the spectral distribution and/or the decay behavior and/or the spatial distribution of the luminescent substance in the document of value. In particular, valuable documents of certain types of valuable documents can have, as a security feature, a luminescent substance specified for the type of valuable document, which is applied to only one side of the valuable document, hereinafter referred to as the front of the valuable document.

Due to the very large number of valuable documents in circulation, for example in the case of banknotes, a mechanical or automatic check of the valuable documents is desirable. For this purpose, the valuable documents can be transported past optical sensors at high speed in corresponding valuable document processing devices, by means of which luminescence properties can be checked during the transport past.

During machine processing, depending on the feed, a document of value can be transported in one of four possible positions, which result from the possible rotations around the longitudinal and transverse axes of the document of value by 180°. For example, if the document of value has a feature on a front left side, this can appear at the top or bottom and left or right depending on the position, for example when looking at the surface of the document of value from above.

Known sensors for luminescent substances usually work in a remission geometry, that is to say that an excitation radiation source for irradiating the document of value with excitation radiation and a detector for detecting luminescent radiation are arranged on the same side of the transport path for the document of value or the document of value. If valuable documents can appear in different positions, then a check of security features applied on one side, in particular also printed luminescent features, requires two sensors that are arranged on opposite sides of the transport path and thus of the valuable document. Both the provision of the sensors and the processing of the signals from the sensors require additional effort.

Out of DE 102 59 293 A1 Although a device for checking the authenticity of banknotes with luminescent substances applied on one side is known, in which the excitation radiation source and detector are arranged on opposite sides of a transport path for valuable documents, the device has electrical or electronic components on different sides of the transport path, which for assembly or installation, and the space requirement has disadvantages.

In EP 3 503 049 A1 a device for detecting a machine-readable security feature of a document of value is described. This has via a transport device which is set up to transport the document of value on a transport level, with a first flat side and a second flat side of the document of value lying opposite this extending parallel to the transport level. Furthermore, the device has a radiation emitter which is arranged on the first flat side and emits radiation in the direction of the first flat side, the radiation being set up to excite luminescent radiation of the security feature of the document of value, and the radiation being further set up to pass at least partially through the document of value . In addition, the device has a sensor which is arranged on the first flat side and receives at least part of the luminescent radiation, a reflector which is arranged on the second flat side and is set up to at least partially reflect the luminescent radiation of the security feature of the document of value to the sensor, and an evaluation unit.

US 4,650,320 describes the detection of luminescent security features in or on documents using a detector. This includes a fiber optic light guide arranged to transmit an interrogation beam originating from a source to a document to be examined. The detector further includes a housing in which a photodiode array is mounted to receive luminescence emitted from the document. The photodiode array is connected to electronic circuitry to distinguish between luminescence due to a security feature and other luminescence emitted from the document and to determine that a security feature has been detected.

EP 2 706 511 A1 discloses an embodiment, an image reading device includes an illumination unit for irradiating a sheet conveyed by a transport unit with visible light and infrared light, an imaging unit for receiving visible light and infrared light reflected from the sheet and forming a visible image, and a to capture an infrared image, and a background element that includes an infrared light weakly reflecting portion positioned within an imaging region of the imaging unit so that it overlaps at least a side edge portion of the sheet and that diffusely reflects visible light and reflects infrared light having a lower reflectivity than the sheet .

In general, it would be advantageous to use arrangements of excitation radiation sources and detectors that are not just for checking valuable documents with homogeneously distributed luminescent substances, but also for checking valuable documents in which luminescent substances are not uniformly distributed and/or only applied to one side of the valuable document.

The present invention is therefore based on the object of providing a method that allows simple checking of valuable documents with luminescent features applied on one side and requires components that can be used easily and flexibly. Furthermore, a corresponding device for carrying out the method should be provided.

The task is solved by a first method with the features of claim 1.

The luminescent radiation excited by excitation of the luminescent substance on the front of the document of value by at least part of the excitation radiation after transmission through the substrate of the document of value is at least partially emitted by the luminescent substance in the direction of the back, and then at least partially after transmission through the document of value on the back of the document of value to withdraw from the document of value.

In principle, in the first method, the document of value can rest in relation to the excitation device. However, it is preferred that, in order to check the document of value, the document of value is transported along a transport path and at least the steps of irradiation and detection are carried out during transport.

The task is also solved by a second method with the features of claim 5.

The luminescent radiation excited by excitation of the luminescent substance of the document of value by at least part of the excitation radiation after transmission through the substrate of the document of value is at least partially emitted by the luminescent substance in the direction of the back in order to then exit on the first side after transmission through the at least the substrate.

The task is further solved by a device with the features of claim 15.

Such a device according to the invention is also referred to below as a testing device.

The detection area of the device is understood to be an area in which at least a section of a valuable document must be located so that excitation radiation can be radiated onto at least part of the section by means of the excitation device and luminescence radiation excited by the irradiation from the section can be detected by means of the detection device.

Excitation device and detection device, or more precisely at least their surfaces from which radiation emerges or enters, are arranged on the same side of the transport path and thus of the document of value therein. This also makes it possible to check the above-mentioned documents of value using the same components if they have a position in which the front side is irradiated with the luminescent substance directly by the excitation device.

To emit excitation radiation suitable for exciting luminescence of the luminescent substance, the excitation device can provide at least one radiation source, for example at least one light-emitting diode and/or a laser, and optionally a filter which is unsuitable for excitation Wavelength components are essentially opaque, as well as a collimating device that concentrates the radiation from the radiation source, for example at least one lens.

The detection device can be designed depending on the properties of the luminescent radiation used for testing. For example, it can include a spectrometric device for the spectrally resolved detection of luminescent radiation or a device for the separate detection of wavelength components of the luminescent radiation in at least two wavelength ranges. The detection device forms detection signals that represent properties of the detected luminescence radiation and sends them to the evaluation device.

The evaluation device is used to check the document of value depending on at least one property of the luminescence radiation detected by the detection device and can be connected to it via a corresponding signal connection. For testing, the evaluation device can preferably carry out the testing step according to one of the methods according to the invention. For this purpose, the evaluation device can, for example, have a processor and a memory connected to the processor, in which a program is stored, when the processor executes the test.

The device can, in particular if the second method according to the invention is to be carried out with the device, be designed in such a way that it is designed to check the documents of value while they are being transported individually along a transport path that leads through the detection area, and in particular in such a way that the excitation device a respective one of the valuable documents in the transport path is illuminated from the first side of the detection area, and that the detection device detects luminescence radiation emanating from the respective value document in the detection area in the transport path in the direction of the first side. This embodiment allows automatic and therefore efficient checking of even large numbers of valuable documents.

Particularly preferably, the excitation device and the detection device can be arranged on the same side of the detection area and/or the transport path. These arrangements have the advantage that no active components of the device need to be arranged on opposite sides of the detection area or transport path in order to be able to check the valuable documents in all possible positions. Since all active components of the testing device are located on the same side of the detection area, a compact design and flexible use of the excitation and detection device are made possible. In particular, the otherwise necessary cabling and synchronization of excitation and detection devices on both sides of the valuable document can be avoided. Overall, the invention thus enables a simplified yet reliable testing of luminescent security features applied to one side of valuable documents. In addition, the arrangement of the excitation and detection device also allows valuable documents with luminescent substances homogeneously distributed in the substrate to be checked, so that the device can be used flexibly.

The present invention therefore also relates to a device for processing valuable documents which have a front side and a back side opposite the front side and which have a substrate and a predetermined luminescent substance applied to the substrate in at least a section of the front side of the document of value, with a feed device for documents of value to be processed, into which documents of value can be introduced and individually issued therefrom, an output device in which processed documents of value can be stored, a transport device for individually transporting documents of value from the feed device along a transport path to the output device, a control device for controlling the transport and / or output device, and a device according to the invention for checking documents of value which have a front side and a back opposite the front side and which have a substrate and a predetermined luminescent substance applied to the substrate in at least a section of the front side of the document of value, wherein the device for testing and the transport device are designed and arranged such that the transport path runs through the detection area of the device for testing, and wherein the control device with the device for testing is connected via a signal connection and is designed to control the transport device and / or the output device depending on results of the device for testing.

The methods are used to test documents of value with a substrate and a luminescent substance applied to the substrate in at least a section of the front of the document of value, that is, documents of value of a type of value document, the documents of value of which have a substrate and a luminescent substance on the substrate in at least a section of the front of the document of value have applied luminescent material. The documents of value therefore comprise a sheet-shaped substrate which has one side has a luminescent substance specified for the value document type in at least one section of its surface. This side is hereinafter referred to as the front side of the substrate, and the side opposite this side is referred to as the back side. The front and back of the document of value refer to those sides of the document of value to which the front and back of the substrate are closest. The luminescent substance is to be seen as part of the document of value. The luminescent substance on the surface of the substrate can preferably be applied there, for example by printing or other forms of application. The luminescent substance can be present as a layer on the surface or can be contained in a layer on the surface. The layer does not need to form the top layer of the document of value and/or be applied directly to the substrate.

The luminescent substance can comprise one or more components and is preferably specified by a value document type of the value document. The value document type of a value document can be given at least by the currency and/or the nominal value and/or, if applicable, the issue. Real valuable documents of this type of valuable document must then have the luminescent substance in at least one section of the front of the valuable document. Particularly preferably, the luminescent substance can emit luminescent radiation in the infrared and/or visual spectral range when excited by the excitation radiation. The value document type can also have other properties, for example a print on the front and/or back of the value document or the presence of a security thread or similar.

It has been found that luminescence can be excited on the front of the document of value when it is illuminated from the back, and that at least some of the luminescent radiation excited at the front propagates to the back and exits the document of value on the back can be detected and used for testing.

The substrate of the document of value is at least partially transparent to the excitation radiation, at least in the area of the luminescent substance applied to the surface. Preferably, the transmittance of the substrate of the document of value for the excitation radiation is at least 10%, preferably at least 15%, particularly preferably at least 25%. For an effective transport of the excitation radiation through the substrate of the document of value, a directed transmission is not necessarily necessary; rather, the radiation transport can also take place diffusively and therefore non-directionally through corresponding scattering contributions. Accordingly, the specified transmission values refer to measurements that capture the transmitted excitation radiation integrally across all exit angles.

Luminescent radiation that was excited at the front and spreads in the substrate towards the back can reach the back, emerge there and then be detected. The substrate is also at least partially transparent to the luminescent radiation, at least in the area of the luminescent substance applied to the surface. The transmission for the luminescent radiation is preferably at least 10%, particularly preferably at least 15%, particularly preferably at least 25%.

Preferably, the substrate is at least partially transparent to optical radiation in at least one wavelength range in the infrared (IR) and/or visual (VIS) range. The wavelength ranges include at least the wavelength of the excitation radiation and the spectrum of the luminescent radiation generated by the luminescent substance.

The substrate preferably comprises at least one polymer layer, in particular made of polypropylene. In the case of pure polymer substrates, the substrate can have at least one further layer underneath the luminescent substance, for example a color-accepting layer or another layer. In the context of the present application, these layers are viewed as components of the substrate.

In other embodiments, the document of value can also have a so-called hybrid substrate, which comprises at least one polymer layer and at least one paper layer connected to the polymer layer.

In the method, only one test device is preferably used to test the luminescence, in which the excitation device and detection device or, more precisely, their radiation exit and entry surfaces are arranged on the same side of the detection area. In the device, the excitation device and detection device or, more precisely, their radiation exit and entry surfaces are preferably arranged on the same side of the detection area. A second device is not necessary. In particular, it is possible for the testing device to have no further radiation source for emitting excitation radiation on the side of the detection area that faces away from the excitation device.

If the document of value is transported past the excitation device and the detection device for testing, a distance in the device between the transport plane in which the document of value is transported and the detection device can preferably be greater than 4 mm, particularly preferably greater than 9 mm. In the method, it is preferred that when detecting the at least part of luminescent radiation by means of the detection device, the distance between the document of value and the detection device is greater than 4 mm, particularly preferably greater than 9 mm. This has the advantage that contact between the valuable document, in particular the transported valuable document, and the closest element of the detection device, for example a window or a lens or another optical element, and thus contamination or damage can be avoided

In the method, the document of value is checked depending on at least one property of the detected luminescent radiation. When testing, at least one property of the detected luminescence radiation is used. Preferably, a spectral property of the detected luminescence radiation or a time behavior of the luminescence radiation, for example a decay behavior, can be tested as a property. In particular, the intensity at a predetermined wavelength or in a narrow wavelength range or the intensity at at least two different wavelengths or wavelength ranges can be used as a spectral property. In particular, if the document of value is irradiated with excitation radiation during transport and the resulting luminescence radiation is at least partially detected, a spatial distribution of the luminescence and thus the Luminescent material can be used. A combination of at least two of the properties mentioned is particularly preferably used. Depending on the type of detection device and the type of test, the property can be given solely by a property of the detection signal of the detection device, for example its level, or can be determined by further evaluation of the detection signal in the evaluation device.

In the case of the methods, it may be preferred that during testing it is checked whether the detected luminescent radiation represents an indication of the presence of the luminescent substance on the front of the document of value. Such a note can be used as an indication of the authenticity of the document of value or its type. The evaluation device of the device can then preferably be designed to check during testing whether the detected luminescent radiation represents an indication of the presence of the luminescent substance on the front of the document of value. At the end of the test, the evaluation device of the device can preferably form or emit an indication signal which shows whether the test has resulted in the indication or not. This indication signal can then be used further in a value document processing device, for example for sorting.

In the second method, it may be preferred that the checking is carried out in such a way that the result of the checking is independent of whether the first page of the document of value is the front of the document of value or the back. In the device, the evaluation device can be designed such that the testing is carried out in such a way that the result of the testing is independent of whether the first Side of the document of value is the front of the document of value or the back. This allows a simple check using very simple means; in particular, prior sorting in terms of location is not necessary to check valuable documents.

In this embodiment, during testing, an intensity of the detected luminescent radiation can preferably be compared with a reference value, which is independent of whether the front side is the first side or not. If the intensity of the detected luminescent radiation exceeds the reference value, this is an indication of the presence of the luminescent substance.

In particular, the reference value can be predetermined in such a way that one or more reference value documents, for example real reference value documents, of the same type of value document as the value document(s) to be examined have are examined using the testing device or a testing device which is designed in the same way, possibly except for the evaluation device. The reference value document or documents therefore also have a front side and a back side opposite the front side. They further comprise the substrate and the predetermined luminescent substance applied to the substrate in at least a section of the front side of the document of value. For this or these reference value documents, the property of the luminescent radiation is then determined, which is emitted by the luminescent substance when the back of the value document is irradiated with excitation radiation and emanates from the back. For the last described embodiment, a corresponding detection is also carried out for the reference document(s), but in which the front side is directly irradiated with excitation radiation. If the property is the strength of the luminescent radiation, can the reference value must be set so that it is below the strength of the luminescence radiation that was recorded for the reference value documents when the back was irradiated.

Alternatively, in the second method, it may be preferred to use at least two test criteria when checking, a first of which is a criterion that the first page is the front of the document of value, and the second test criterion is a criterion that the first page is the back of the document of value. In the device, the evaluation device can be designed to use at least two test criteria when checking, of which a first is a criterion that the first page is the front of the document of value, and the second test criterion is a criterion that the first Side is the back of the document of value. This procedure has the advantage that different and therefore more precise criteria can be used for the presence of the luminescent substance on the first side or second side, so that the test becomes more precise. In particular, the test criteria can use different reference values with which the property of the detected luminescent radiation, for example its strength, is compared. If the front of the document of value and thus the luminescent substance is irradiated directly with excitation radiation, stronger luminescence radiation can result, for example, than in the case of irradiation after passage through the substrate and subsequent passage of the excited luminescence radiation through the substrate, with weakening generally occurring through the substrate.

Preferably, in the method, in particular in the last described embodiment, the check also determines whether the first page the front or the back is. A signal can then be formed and sent that represents whether the first page is the front or the back of the document of value. This result can be compared in a valuable document processing device with other test results from which conclusions can be drawn about the position of the valuable document. In the case of the device, the evaluation device is preferably designed in such a way that when checking it is also determined whether the first page is the front or the back. A signal can then be formed and sent that represents whether the first page is the front or the back of the document of value. For this purpose, the device can preferably have an interface via which the signal mentioned can be emitted. This interface can also be used to transmit other signals.

A further preferred embodiment of the method further comprises detecting a position of the document of value, the position reflecting whether the first side of the document of value is the front or the back. In the method, the checking can then preferably be carried out depending on the recorded position of the document of value. Capturing the situation need only consist of capturing relevant information provided by another facility. The value document processing device can then have a position determination device, by means of which a position of the value document can be determined, the position reflecting whether the first side of the value document is the front or the back, and which emits a position signal to the testing device, more precisely its evaluation device, which Position of the document of value reflects. The position determination device can, for example, have an image sensor operating in the visible wavelength range, by means of which a remission or transmission image of at least a section of the document of value can be captured. In the testing device, the evaluation device can then preferably have an interface by means of which it can receive at least one signal that reflects the position of the document of value, the position reflecting whether the first side of the document of value is the front or the back, and is further designed to do so be to carry out the checking depending on the location of the document of value. This embodiment allows a very precise test, since the expected properties of the detected luminescence radiation depend on the position of the document of value and the test can be carried out differently for the possible positions. For example, reference values for the strength of the detected luminescence radiation could be specified depending on the position of the document of value.

According to the invention, the first method further comprises reflecting a portion of the excitation radiation, which has emerged after transmission through the document of value on the front of the document of value, at least partially back onto the document of value, and exciting the luminescent substance to emit luminescent radiation through the reflected part. In the first method, at least part of the luminescence radiation excited by the reflected part of the excitation radiation is also detected after transmission to the back of the document of value and exiting the document of value.

Accordingly, according to the invention, the second method includes reflecting a part of the excitation radiation, which, after transmission through the document of value, on a second, opposite to the first Side of the document of value has emerged, at least partially back onto the document of value and stimulating the luminescent substance to emit luminescent radiation through the reflected part. In the second method, at least part of the luminescence radiation excited by the reflected part of the excitation radiation and emanating from the first page of the document of value is also detected. If the second side of the document of value is the front of the document of value, the luminescent radiation is excited on the front; A part of it is emitted into the document of value and passes through the substrate to the first side, i.e. the back, where it emerges at least partially from the document of value and thus emanates from the first side. If, on the other hand, the second side of the document of value is the back of the document of value, the reflected part of the excitation radiation at least partially penetrates the substrate and excites luminescence radiation on the front of the document of value, the first page. Part of this luminescent radiation is emitted into the half-space in front of the front, i.e. it also comes from the first page of the document of value.

These embodiments of the first and second methods have the advantage that excitation radiation which has passed through the document of value without having excited luminescence is at least partially directed back onto the document of value and can generate additional luminescence radiation which can be detected together with the luminescence radiation. which was excited by non-reflected excitation radiation. In this way, with excitation radiation of the same strength, significantly more or stronger luminescence radiation is detected, which increases the accuracy of the test. The luminescence radiation excited by the reflected portion of the excitation radiation is not detected by the Portion of the luminescent radiation that was generated by the non-reflected portion of the excitation radiation, separated, so that the detected luminescent radiation includes both the luminescent radiation generated by the non-reflected excitation radiation and the luminescent radiation generated by the reflected excitation radiation. This or its at least one property is used for checking.

In the method, the excitation radiation is preferably reflected with a reflectance of more than 50%, particularly preferably more than 90%.

Alternatively or additionally, in the first method according to the invention, it further comprises reflecting luminescent radiation, which was generated by exciting the luminescent substance on the front of the document of value by means of the excitation radiation and is emitted on the front of the document of value, at least partially back onto the document of value . In the first method, the reflected luminescence radiation is then at least partially detected after transmission to the back of the document of value and exit from the document of value.

Accordingly, in the second method according to the invention, luminescent radiation, which was generated by exciting the luminescent substance on the front of the document of value by means of the excitation radiation and emanates from a second side of the document of value opposite the first, is reflected at least partially back onto the document of value includes. The second method continues with the acquisition the reflected luminescence radiation is also recorded at least partially after transmission to the first side of the document of value and emerging from the document of value on the first page.

Even in these embodiments or developments of the first or second method, the reflected luminescent radiation cannot be separated from the non-reflected luminescent radiation during detection. Therefore, the detected luminescent radiation includes both the non-reflected luminescent radiation and the reflected luminescent radiation. This or its at least one property is used for checking.

In the process, the luminescent radiation is preferably reflected back with a reflectance of more than 50%, particularly preferably more than 90%.

These embodiments have the advantage that portions of the basically undirected luminescence radiation, which would otherwise leave the detection area in the direction of the second side of the detection area and would not be detected, can be at least partially detected after transmission through the document of value. The detected luminescent radiation is therefore stronger than an arrangement without a reflection device, which increases the accuracy of the detection and thus also the testing.

According to the invention, the device has a reflection device for these embodiments of the method, the excitation radiation emanating from a second side of the document of value opposite the first side and/or from a second side opposite the first side The luminescence radiation emanating from the document of value is reflected back into the detection area or onto the document of value therein. The device therefore only has electrical elements on the same side of the detection area; on the other side there is only the reflection device, which does not require any electrical control or signal connection. In the device, the reflection device preferably has a degree of reflection of more than 90% for the excitation radiation or the luminescence radiation.

Particularly strong luminescence radiation is obtained when both excitation and luminescence radiation are reflected in the method and in the device. This embodiment has the further advantage that the reflection device only needs to be suitably designed, for which particularly preferably no additional components are necessary.

Preferably, the reflection device is set up to reflect in a directed manner the at least part of the excitation radiation emerging from the front of the substrate and/or the at least part of the luminescent radiation emitted by the luminescent substance in the direction of the reflection device. Accordingly, in the methods, the at least part of the excitation radiation emerging from the front of the substrate and/or the at least part of the luminescent radiation emitted by the luminescent substance is preferably reflected in a directed manner. Thus, the excitation radiation and/or the luminescence radiation, which exits in the area of the detection device on the front of the substrate and / or the document of value and would therefore be lost, thrown back towards the detection device. The reflection device is preferably spaced from the detection area. Preferably, the distance between the reflection device and the detection area, particularly preferably the transport path, is between 1 and 20 mm, in particular between 3 and 12 mm, in particular approximately 10 mm. This avoids contact between the reflection device and the valuable documents or the transport device, which could lead to mechanical damage to the valuable documents, the transport device and/or the reflection device.

According to the invention, in the method the excitation and/or luminescence radiation is at least approximately focused on the transported documents of value when reflected. In the device, the reflection device is designed according to the invention in such a way that it focuses the reflected excitation and/or luminescence radiation into the detection area. Preferably, a focal plane or focal point of the reflection device lies less than 2 mm above and less than 2 mm below a transport plane along which the documents of value are transported. This has the advantage that the reflected excitation radiation can excite more luminescence radiation or at least the Luminescence radiation approximately focused in the value document can be better detected, in particular by means of the detection device.

Preferably, the reflection device has at least one cylindrical hollow mirror and/or at least one reflectively coated convex, in particular plano-convex, cylindrical lens, which has a reflective surface, the focal line of which is in a measuring plane of the detection device and/or in the vicinity of the front side and/or on the front of the document of value, in particular transported by the transport device. The distance between the focal line and the measuring plane and/or the front of the document of value is preferably less than 20% of the focal length of the reflection device, in particular less than 2 mm. The cylindrical concave mirror is preferably positioned so that the cylinder axis lies approximately in the measuring plane of the testing device. In the case of the cylindrical lens, the curved side of the cylindrical lens is preferably coated with a reflective coating. In both variants, the scattered light and/or the luminescent radiation that arises near the focal line is reflected back approximately into the focal line by the mirror or the coated lens surface. A particular advantage of using a plano-convex lens with a reflectively coated curved side compared to the cylindrical concave mirror is that there is a flat surface on the banknote transport plane that is robust against banknote abrasion and can be easily cleaned.

Alternatively or additionally, the reflection device has at least one Fresnel cylindrical hollow mirror and/or at least one reflectively coated Fresnel cylindrical lens, which has two or more has reflective surfaces which have different radii of curvature and whose focal lines lie in a measuring plane of the detection device and / or near the front and / or on the front of the document of value, in particular transported by the transport device. In the case of a Fresnel cylindrical concave mirror with several cylindrical surfaces with different radii, these are positioned so that a common focal line results that lies in the measuring plane. The distance between the focal line and the measuring plane and/or the front of the document of value is preferably less than 20% of the focal length of the reflection device, in particular less than 2 mm. The scattered excitation light and/or the luminescence radiation that arises near the focal line is reflected back to the focal line by the individual mirrors in a significantly larger angular range than is the case with a single cylindrical concave mirror. Similarly, in a Fresnel cylindrical lens, several cylindrical lenses with different radii are combined in such a way that a Fresnel cylindrical lens is created, the curved sides of which are reflectively coated and which has a single focal line that lies in the measuring plane. A particular advantage of using a plano-convex Fresnel cylindrical lens over a Fresnel cylindrical concave mirror is that there is a flat surface towards the banknote transport plane that is robust against banknote abrasion and can be easily cleaned. The Fresnel arrangement allows larger angular ranges to be reflected back than with a simple cylindrical lens.

It can advantageously be provided that the reflecting surface or at least one of the reflecting surfaces has two ends in the direction of the respective cylinder axis and the reflecting surface or at least one of the reflecting surfaces in the area of at least one of the two ends is curved concavely, in particular spherically or aspherically, towards the cylinder axis and / or in the area of at least one of the two ends of the reflecting surface or the at least one reflecting surface is a plane mirror, in particular perpendicular to the cylinder axis , is provided. Concave ends of the reflective cylinder surface reduce the edge drop of the cylinder reflection in the area of the ends, so that the excitation radiation or luminescence radiation is efficiently reflected towards the document of value or sensor, which results in a correspondingly higher intensity of the detected luminescence radiation. Plane mirrors can “fold back” part of the scattered radiation, which would be reflected by the concave mirror(s) into an area that lies outside the detection range of the detection device, back into the detection area and thereby also reduce the edge falloff and increase the intensity of the detected luminescence radiation. Compared to concave ends, plane mirrors are simpler and cheaper to manufacture.

Alternatively or additionally, the reflection device can have at least one spherical concave mirror and / or at least one reflectively coated spherical convex lens, in particular plano-convex lens, which has a reflecting surface whose focal point is in a measuring plane of the detection device and / or near the front and / or lies on the front of the document of value, in particular transported by the transport device. In one embodiment, the distance between the focal point and the measuring plane and/or the front of the document of value is less than 20% of the focal length of the reflection device, in particular less than 2 mm.

Alternatively or additionally, the reflection device can have at least one spherical Fresnel concave mirror and/or at least one reflectively coated spherical Fresnel lens, which has two or more reflecting surfaces which have different radii of curvature and which are positioned so that there is a common one Focal point results, which lies in a measuring plane of the detection device and / or near the front and / or on the front of the document of value transported, in particular by the transport device. The distance between the focal point and the measuring plane and/or the front of the document of value is preferably less than 20% of the focal length of the reflection device, in particular less than 2 mm.

In the above-mentioned variants with spherical (Fresnel) reflectors, the scattered light and/or the luminescent radiation that arises near the focal point of a reflector is reflected back approximately to the starting point by the reflector. A particular advantage of using a coated plano-convex lens compared to a concave mirror is that there is a flat surface towards the banknote transport plane that is robust against banknote abrasion and can be easily cleaned. A Fresnel arrangement allows larger angular areas to be reflected back. With this reflection, in one embodiment the reflection cannot produce an exact image at the starting point due to the scattering effect of the substrate of the document of value. However, when testing a substrate with a low scattering effect, for example a polymer substrate, an approximately exact image may be possible.

The above-mentioned variants with spherical (Fresnel) reflectors are preferably used when the irradiation is not, at least approximately, linear illumination or irradiation of the document of value by the irradiation device, but rather individual tracks on the document of value with finite , in particular clear, distances between them are irradiated. In these cases, analogous to the variants described above with cylindrical reflectors or Fresnel reflectors, the excitation radiation or luminescence radiation is reflected with a single spherical reflector per track towards the document of value or in the direction of the detector located behind the document of value. For this purpose, the reflection device has a plurality of spherical reflectors which are arranged offset from one another along a direction perpendicular to the transport direction of the document of value, each spherical reflector being replaced by a spherical concave mirror, a reflectively coated spherical convex lens, a spherical Fresnel concave mirror or a reflectively coated spherical Fresnel lens is formed.

Alternatively or additionally, the reflection device can have at least one retroreflector, which is designed to reflect the incident excitation radiation and / or luminescence radiation largely independently of the direction of incidence and the orientation of the reflector in the direction from which they came or are . ie towards the document of value or the luminescent security feature. The retroreflector can preferably consist of a plurality of three plane mirrors (“cat's eye”) arranged in pairs perpendicular to one another or, alternatively, a plurality of small, transparent beads Include glass or polymer. In a particularly preferred embodiment, the large number of transparent beads are additionally coated with a reflective metallic coating on the back.

Preferably, the transport device is set up to transport the document of value in a transport direction relative to the irradiation device, and the reflection device is arranged offset against the transport direction with respect to the irradiation device, in particular an illumination optics of the irradiation device. In this embodiment, the reflecting surface of the reflection device, for example the cylindrical and/or spherical and/or Fresnel mirror, is arranged slightly offset from the transport direction with respect to the lighting optics. This causes the reflected excitation radiation to be offset by twice the amount. The luminescences excited by this mirrored radiation can contribute to the detection signal for a longer period of time since they have to be transported further until they have left the detection range of the detection device. In addition to increasing the intensity of the detected luminescence radiation on high-speed machines (with transport speeds of, for example, >3m/s or >5m/s or >7m/s), such an arrangement with an offset increases the selectivity with which slow and fast decay time constants of luminescence can be distinguished , since luminescence radiation in particular with a slow decay time is largely transported out of the detection area of the test device and is reflected back into the detection area by the reflector with an offset. This allows for more accurate authenticity testing, as typical luminescent feature substances have longer decay times than possible interfering background fluorescence.

Alternatively or in addition to the offset, the reflection device, such as the cylindrical or spherical mirror, can also be tilted in its alignment with the perpendicular of the transport plane.

With the invention, it is now possible to check a document of value with a luminescent feature without the need for sensors on two sides that check for remission and/or transmission. In comparison with the prior art, a simple structure of a device for checking a document of value and a device for processing documents of value is thus made possible. In particular, not only the direct structure is simplified here, but also the control, evaluation and wiring of the excitation and detection device, since instead of at least two devices for testing remission and transmission, only one device is necessary. In addition, due to the arrangement of the excitation device and the detection device on the same side, which is directed towards the document of value to be checked, an arrangement that optimizes installation space is possible. Furthermore, energy consumption and maintenance costs are reduced due to the optimized arrangement and the low requirement for components.

Furthermore, it is now possible to set the distances to transport elements, in particular to a valuable document transport level, precisely and safely during adaptation. Furthermore, due to the arrangement of the device for testing on only one side of the value document transport level, it is possible that no coordination of the position between the excitation device and the detection device is necessary, since these two components can already be provided as essentially one assembly.

Furthermore, with the invention, a simpler synchronization between the detection device and the excitation device is possible compared to the prior art with several detection and excitation devices, whereby the detection device and the excitation device, for example, do not excite or detect at the same time.

Fig. 1

eine schematische Ansicht eines Ausführungsbeispiels für eine Wertdokumentbearbeitungsvorrichtung;

Fig. 2

eine schematische Darstellung eines Beispiels für eine Prüfvorrichtung der Wertdokumentbearbeitungsvorrichtung in Fig. 1, in einer Seitenansicht quer zu einer Transportrichtung und in einer Blattebene eines Wertdokuments,

Fig. 3A bis 3D

schematische Seitenansichten eines Wertdokuments mit einem einseitig aufgebrachten Lumineszenzstoff in verschiedenen Lagen relativ zu einer Anregungs- und einer Erfassungseinrichtung der Prüfvorrichtung in Fig. 2,

Fig. 4

ein schematisches Ablaufdiagramm eines ersten Beispiels für ein Verfahren zum Prüfen eines Wertdokuments mit einem nur einseitig aufgebrachten Lumineszenzstoff,

Fig. 5

ein schematisches Ablaufdiagramm eines weiteren Beispiels für ein Verfahren zum Prüfen eines Wertdokuments mit einem nur einseitig aufgebrachten Lumineszenzstoff.

Fig. 6

ein schematisches Ablaufdiagramm eines Schritts S16 in dem Verfahren in Fig. 5,

Fig. 7

ein schematisches Ablaufdiagramm eines fünften Beispiels für ein Verfahren zum Prüfen eines Wertdokuments mit einem nur einseitig aufgebrachten Lumineszenzstoff,

Fig. 8

eine schematische Darstellung eines weiteren Beispiels für eine Prüfvorrichtung der Wertdokumentbearbeitungsvorrichtung in Fig. 1, in einer Seitenansicht quer zu einer Transportrichtung und in einer Blattebene eines Wertdokuments,

Fig. 9A und 9B

schematische Darstellungen von Verläufen von verschiedenen Anteilen der Anregungsstrahlung und der Lumineszenzstrahlung bei Verwendung der Prüfvorrichtung in Fig. 5 in einem Wertdokument mit einem einseitig aufgebrachten Lumineszenzstoff in zwei verschiedenen Lagen relativ zu einer Anregungs- und einer Erfassungseinrichtung der Prüfvorrichtung in Fig. 5,

Fig. 10

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht;

Fig. 11

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht;

Fig. 12

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht;

Fig. 13

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht;

Fig. 14

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht;

Fig. 15

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht;

Fig. 16

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht; und

Fig. 17

ein Beispiel einer Reflexionseinrichtung einer Prüfvorrichtung in Fig. 8 in einer Seitenansicht.

Further advantages, features and possible applications of the present invention result from the following description in connection with the figures. Show it:

Fig. 1

a schematic view of an exemplary embodiment of a value document processing device;

Fig. 2

a schematic representation of an example of a testing device of the value document processing device in Fig. 1 , in a side view transverse to a transport direction and in a sheet level of a document of value,

3A to 3D

schematic side views of a document of value with a luminescent substance applied on one side in different positions relative to an excitation and a detection device of the testing device in Fig. 2 ,

Fig. 4

a schematic flow chart of a first example of a method for checking a document of value with a luminescent substance applied to only one side,

Fig. 5

a schematic flow diagram of a further example of a method for checking a document of value with a luminescent substance applied to only one side.

Fig. 6

a schematic flowchart of a step S16 in the method in Fig. 5 ,

Fig. 7

a schematic flow diagram of a fifth example of a method for checking a document of value with a luminescent substance applied to only one side,

Fig. 8

a schematic representation of a further example of a testing device of the value document processing device in Fig. 1 , in a side view transverse to a transport direction and in a sheet level of a document of value,

Figures 9A and 9B

Schematic representations of curves of different proportions of the excitation radiation and the luminescence radiation when using the test device in Fig. 5 in a document of value with a luminescent substance applied on one side in two different positions relative to an excitation and a detection device of the testing device Fig. 5 ,

Fig. 10

an example of a reflection device of a testing device in Fig. 8 in a side view;

Fig. 11

an example of a reflection device of a testing device in Fig. 8 in a side view;

Fig. 12

an example of a reflection device of a testing device in Fig. 8 in a side view;

Fig. 13

an example of a reflection device of a testing device in Fig. 8 in a side view;

Fig. 14

an example of a reflection device of a testing device in Fig. 8 in a side view;

Fig. 15

an example of a reflection device of a testing device in Fig. 8 in a side view;

Fig. 16

an example of a reflection device of a testing device in Fig. 8 in a side view; and

Fig. 17

an example of a reflection device of a testing device in Fig. 8 in a side view.

A valuable document processing device 10 in Fig. 1 , in the example a device for processing valuable documents 12 in the form of banknotes, is designed for sorting valuable documents depending on the authenticity of processed valuable documents checked by means of the valuable document processing device 10.

It has a feed device 14 for feeding valuable documents, an output device 16 for receiving processed, ie sorted, documents Documents of value, and a transport device 18 for transporting isolated documents of value from the feed device 14 to the output device 16.

In the example, the feed device 14 comprises an input compartment 20 for a stack of valuable documents and a separator 22 for separating valuable documents from the stack of valuable documents in the input compartment 20 and making them available for or fed to the transport device 18. Valuable documents are fed to the transport device 18 in the same position they have occupied the input compartment 20, that is, without changing their position, for example without turning or rotating.

In the example, the output device 16 comprises three output sections 24, 25 and 26, into which processed documents of value can be sorted depending on the result of the processing, in the example testing. In the example, each of the sections includes a stacking compartment and a stacking wheel, not shown, by means of which documents of value supplied can be stored in the stacking compartment.

The transport device 18 has at least two, in the example three, branches 28, 29 and 30, at the ends of which one of the output sections 24 or 25 or 26 is arranged, and at the branches via switches 32 and 34 that can be controlled by control signals, by means of which Value documents can be fed to the branches 28 to 30 and thus to the output sections 24 to 26 depending on control signals.

On a transport path 36 defined by the transport device 18 between the feed device 14, in the example more precisely the separator 22, and the first switch 32 in the transport direction T after the separator 22, a sensor device 38 is arranged, which detects properties of the valuable documents during the transport of valuable documents and forms sensor signals that represent the properties. In this example, the sensor device 38 has an optical reflectance sensor 40, which captures a reflectance color image of the valuable document, an optical transmission sensor 42, which captures a transmission image of the valuable document, and a testing device 44 for checking luminescence properties of valuable documents of a predetermined valuable document type.

A machine control and evaluation device 46 is connected to the sensor device 38 and the transport device 18, in particular the switches 32 and 34, via signal connections. In conjunction with the sensor device 38, it classifies a valuable document into one of several predetermined sorting classes depending on the signals from the sensor device 38 for the valuable document. These sorting classes can be predetermined depending on an authenticity value determined using the sensor data. In other exemplary embodiments, the sorting class can also be determined, for example, depending on a status value for a respective value document determined using the sensor data.

In the example, the values “counterfeit”, “suspected of counterfeit” or “genuine” can be used as authenticity values. Depending on the sorting class determined, the machine control and evaluation device 46 controls the transport device 18, here more precisely the switches 32 and 34, by emitting control signals, so that the document of value is sent according to its value The sorting class determined during the classification is output into an output section of the output device 16 assigned to the class. The assignment to one of the specified sorting classes or the classification takes place depending on criteria specified for assessing the authenticity, which depend on at least part of the sensor data.

For this purpose, the machine control and evaluation device 46 has, in particular, in addition to corresponding interfaces for the sensor device 38 or its sensors and the testing device 44, a processor 48 and a memory 50 connected to the processor 48, in which at least one computer program with program code is stored Execution of the processor 48 controls the device, in particular the sensor signals of the sensor device 38, in particular for determining a sorting class of a processed document of value, evaluated and controls the transport device 18 according to the evaluation.

The machine control and evaluation device 46 determines from the sensor signals of the sensor device 38 during a sensor signal evaluation at least one value document property that is relevant for checking the banknotes with regard to their authenticity. Preferably several of these properties are determined. In this example, a transmission image and a reflection image are determined as optical value document properties and, by means of the testing device 44, the presence of a predetermined luminescence property is determined as a further property.

Depending on the value document properties, the machine control and evaluation device 46 determines for the various sensors or the testing device respectively sorting signals which represent whether the determined document properties represent an indication of the authenticity of the document of value or not. As a result of these signals, corresponding data can be stored in the machine control and evaluation device 46, for example the memory 50, for later use. Depending on the sorting signals, the machine control and evaluation device 46 then determines an overall result for the test according to a predetermined overall criterion and, depending on the result, forms the sorting or control signal for the transport device 18.

To process valuable documents 12, valuable documents 12 inserted into the input compartment 20 as a stack or individually are separated by the separator 22 and fed individually to the transport device 18, which transports the isolated valuable documents 12 past the sensor device 38. This records the properties of the documents of value 12, with sensor signals being formed which reflect the properties of the respective document of value. The machine control and evaluation device 46 detects the sensor signals, determines a sorting class, in the example an authenticity class, of the respective document of value and, depending on the result, controls the switches in such a way that the documents of value are placed in one of the respective sorting class in accordance with the determined sorting class assigned output section are transported.

In the present example, documents of value 12 of a type of value document are checked, in which the documents of value 12 have a front side 72 and a back side 75 opposite the front side (cf. Fig. 3 ) and a substrate 70 and one on the substrate 70 in at least one section the front 72 of the valuable document 12 include predetermined luminescent substance 73 (cf. 3A to 3D ). In particular, it is checked whether a respective document of value has a predetermined luminescent substance applied, in particular on a substrate 70 of the document of value, in at least a section of the front side 72 of the document of value.

To determine a sorting class based on this property of a respective document of value, the testing device 44 is used to examine a document of value, which in the example is structured as follows (cf. Fig. 2 ).

The testing device 44 has a detection area 60 in which a document of value must be located in order to be checked with the testing device. The transport path 36 leads through this. The testing device 44 has a sensor part 62 and an evaluation device 64. The sensor part 62 comprises an excitation device 66 for irradiating a first side of an individual value document in the detection area 60 from a first side of the detection area with excitation radiation 67, which serves to excite the luminescent substance to emit luminescent radiation, and a detection device 68 for detecting by means of the Excitation radiation of excited luminescence radiation 69 emanating from the first side of the document of value 12 in the detection area 60 in the direction of the first side of the detection area 60. The arrangement and the properties of the sensor part 62, and more precisely of the excitation device 66 and detection device 68, determine the extent and position of the detection area. In the present example, the testing device 44 is designed in this way and arranged that the transport path 36 runs through the detection area 60. As far as we are talking about a first side of the detection area or a first side of a valuable document or substrate below, this means the side that faces the excitation device 66 or the sensor part 62. The sensor part 62 is therefore located on the first side of the detection area 60.

In this exemplary embodiment, the excitation device 66 is designed to emit excitation radiation 67 in the infrared spectral range into the detection area 60. In particular, the excitation radiation 67 comprises infrared excitation radiation which is suitable for exciting luminescence of the luminescent substance of the specified document of value or of documents of value of the specified document type. Although it is sufficient that an exit surface, via which the excitation device 66 emits the excitation radiation 67 into the detection area 60, is arranged on one side of the detection area 60, in this example the excitation device 66 is arranged overall on one side of the detection area 60.

In the example, the excitation device 66 of the sensor part 62 generates a linear distribution of the excitation radiation 67 on the document of value 12 or substrate 70. The line preferably runs transversely to the transport direction. In other exemplary embodiments, however, a different irradiation pattern can also be used.

The detection device 68 is arranged on the same side of the detection area 60 and thus of the transport path 36 as the excitation device 66. In other exemplary embodiments, however, it may be sufficient that only one entry surface for luminescent radiation, which emanates from a document of value in the detection area 60, is arranged on the same side of the detection area 60 as the exit area of the excitation device. The detection device 68 is designed in particular to detect luminescence radiation 69 emanating from a document of value 12 in the detection area 60, which was generated by irradiating the document of value 12 with excitation radiation 67 of the excitation device 66 and emanates from the document of value 12. It then generates detection signals that represent properties of the luminescent radiation, in the example the strength of the detected luminescent radiation.

The detection device 68 preferably has a plurality of detection elements corresponding to the excitation device 66 and optionally an optical device, which are designed and arranged in such a way that the detection elements can each detect the excited luminescence radiation from a section of the detection area 60 assigned to the respective detection element and corresponding detection signals are formed. The optical device has filters that suppress optical radiation from a wavelength range in which the luminescent radiation does not lie. These sections are arranged along a line transverse to the transport direction T.

The working distance between the sensor part 62 or the detection device 68 and the document of value 12 in the transport path 36 is preferably between 3 and 12 mm; in the example the distance is approximately 10 mm. In other exemplary embodiments, smaller or larger distances can also be provided.

The distance between the detection device 68 and the valuable document 12 in the transport path or the transport plane is preferably greater than 4mm.

The testing device 44 further has the evaluation device 64 for checking the value document 12 depending on at least one property of the detected luminescence radiation 69, which was detected by means of the detection device 68. In addition, in this exemplary embodiment it serves to control the excitation device 66 and the detection device 68. To carry out the testing, the evaluation device 64 has a processor, a memory connected to the processor and at least one interface for exchanging signals and / or data with the excitation device 66, the detection device 68 and the machine control and evaluation device 46. In Fig. 3 Only one interface for the excitation and detection device and one interface for the machine control and evaluation device are shown. In other exemplary embodiments, the interface for the excitation and detection devices can also be replaced by two separate interfaces for the excitation and detection devices. A computer program is also stored in the memory of the evaluation device 64, when executed by the processor, the evaluation device carries out at least parts of a method for checking documents of value described below.

For this purpose, the excitation device 66, the detection device 68 and the evaluation device 64 are connected to one another via signal connections, so that the evaluation device 64 detects the detection signals of the detection device 68, optionally controls the excitation device 66, and can evaluate the detected detection signals or use them to check the document of value.

The testing device 44 is designed to check valuable documents of the specified value document type with regard to their luminescence.

An in Fig. 3a Value document 12 of the specified value document type shown schematically and not to scale in a sectional view perpendicular to the surface of the document of value has a substrate 70, in the present example a polymer substrate containing polypropylene with an ink-accepting layer present thereon, and on a front side 72 of the substrate 70 on a section of the surface applied to the substrate, printed in the example, a luminescent substance 73 specified for the value document type. The section with the luminescent substance forms a security feature or luminescent feature 74.

The luminescent substance or luminescent substances or luminescent substances used for the luminescent feature can be organic, organometallic and/or inorganic luminescent substances. Luminescence features in which both the excitation and the emission are in the IR range are particularly suitable, since particularly low scattering losses in the substrate and thus particularly high intensities can be expected when measuring from the back through the substrate.

As the wavelength increases, the detection of luminescence radiation can become technically more complex (e.g. due to it being more complex or more expensive detectors, increased background noise), and substrate-specific absorptions can occur, which favor or disadvantage certain wavelength ranges, particularly in cellulose-based substrates. In a preferred embodiment, the luminescence radiation of the luminescence feature is in the range between 750 nm and 1,600 nm. A good compromise between easy detectability and scattering losses is achieved here. On the other hand, using a security feature with a luminescence wavelength whose detection is technically complex, especially a wavelength above 1100 nm, can increase the security against forgery of the valuable document, since a possible forger can only detect the luminescence radiation of the security feature with difficulty.

Examples of such luminescent substances are doped inorganic pigments with the dopants neodymium or ytterbium or erbium or thulium or holmium or other rare earths or combinations thereof, or doped with certain transition metals. Also preferred are organometallic complexes with neodymium or ytterbium or erbium or thulium or holmium or certain organic dyes.

• Oxide, insbesondere 3- und 4-wertige Oxide wie z.B. Titanoxid, Aluminiumoxid, Eisenoxid, Boroxid, Yttriumoxid, Ceroxid, Zirconoxid, Bismutoxid, sowie komplexere Oxide wie z.B. Granate, darunter unter anderem z.B. Yttrium-Eisen-Granate, Yttrium-Aluminium-Granate, Gadolinium-Gallium-Granate; Perowskite, darunter unter anderem Yttrium-Aluminium-Perowskit, Lanthan-Gallium-Perowskit; Spinelle, darunter unter anderem Zink-Aluminium-Spinelle, Magnesium-Aluminium-Spinelle, Mangan-Eisen-Spinelle; oder Mischoxide wie z.B. ITO (Indiumzinnoxid);
• Oxyhalogenide und Oxychalkogenide, insbesondere Oxychloride wie z.B. Yttriumoxychlorid, Lanthanoxychlorid; sowie Oxysulfide, wie z.B. Yttriumoxysulfid, Gadoliniumoxysulfid;
• Sulfide und andere Chalkogenide, z.B. Zinksulfid, Cadmiumsulfid, Zinkselenid, Cadmiumselenid;
• Sulfate, insbesondere Bariumsulfat und Strontiumsulfat;
• Phosphate, insbesondere Bariumphosphat, Strontiumphosphat, Calciumphosphat, Yttriumphosphat, Lanthanphosphat, sowie komplexere phosphatbasierte Verbindungen wie z.B. Apatite, darunter unter anderem Calciumhydroxylapatite, Calciumfluoroapatite, Calciumchloroapatite; oder Spodiosite, darunter z.B. Calcium-Fluoro-Spodiosite, Calcium-Chloro-Spodiosite;
• Silikate und Aluminosilikate, insbesondere Zeolithe wie z.B. Zeolith A, Zeolith Y; zeolithverwandte Verbindungen wie z.B. Sodalithe; Feldspate wie z.B. Alkalifeldspate, Plagioklase;
• weitere anorganische Verbindungsklassen wie z.B. Vanadate, Germanate, Arsenate, Niobate, Tantalate.

Examples of suitable inorganic matrices are:

• Oxides, in particular 3- and 4-valent oxides such as titanium oxide, aluminum oxide, iron oxide, boron oxide, yttrium oxide, cerium oxide, zirconium oxide, bismuth oxide, as well as more complex oxides such as garnets, including, among others, yttrium-iron garnets, yttrium-aluminum garnets , gadolinium gallium garnets; Perovskites, including, but not limited to, yttrium aluminum perovskite, lanthanum gallium perovskite; Spinels, including under other zinc-aluminum spinels, magnesium-aluminum spinels, manganese-iron spinels; or mixed oxides such as ITO (indium tin oxide);
• Oxyhalides and oxychalcogenides, especially oxychlorides such as yttrium oxychloride, lanthanum oxychloride; as well as oxysulfides, such as yttrium oxysulfide, gadolinium oxysulfide;
• sulfides and other chalcogenides, for example zinc sulfide, cadmium sulfide, zinc selenide, cadmium selenide;
• Sulfates, especially barium sulfate and strontium sulfate;
• Phosphates, in particular barium phosphate, strontium phosphate, calcium phosphate, yttrium phosphate, lanthanum phosphate, as well as more complex phosphate-based compounds such as apatites, including, among others, calcium hydroxyapatites, calcium fluoroapatites, calcium chloroapatites; or spodiosites, including, for example, calcium fluoro-spodiosites, calcium chloro-spodiosites;
• Silicates and aluminosilicates, especially zeolites such as zeolite A, zeolite Y; zeolite-related compounds such as sodalites; Feldspars such as alkali feldspars, plagioclase;
• other inorganic compound classes such as vanadates, germanates, arsenates, niobates, tantalates.

As in 3A to 3D Shown schematically in a side view, such a value document of the specified value document type can be present in four different positions: with the front 72 on a first side of the detection area 60 and therefore facing the excitation device 66 and the security feature 74 on the left ( Fig. 3A ) or right ( Fig. 3B ) or with the front 72 on a second side opposite the first side of the detection area, or the back 75 on the first side of the detection area 60 and therefore facing the excitation device 66 and the security feature 74 on the right ( Fig. 3D ) or left ( Fig. 3C ). In other exemplary embodiments, the security feature 74 can also be applied symmetrically. In this case, only two layers can be distinguished: Figures 3A and 3B or. Figures 3C and 3D are equivalent to.

In this exemplary embodiment, it is assumed that the document of value 12 is transported in one of the last two layers or the last of the two layers in the transport path 36, in which the back 75 of the document of value faces the excitation device 66. For this purpose, the stack of valuable documents 12, which is fed to the separator 22, can have valuable documents 12 in one of the last two layers or the last of the two layers. When separating, the layers remain unchanged, so that the valuable documents 12 are transported in the respective position along the transport path 36. The documents of value in the stack can have the same layer or different layers from one another.

Using the transport device 18 and the testing device 44, the following is now carried out: Fig. 4 illustrated method for checking a value document is carried out for each of the value documents, in which the steps are partially carried out in parallel:
In step S10, the transport device 18 transports the document of value 12 through the detection area 60 and past the excitation device 66. The first side of the document of value 12, which faces the excitation device 66, is the back 75 of the document of value 12, that is to say that the document of value is in a position in which the back 75 of the document of value is on the first side of the detection area 60 or the excitation device 66 faces (cf. Figures 3C and 3D ).

Meanwhile, in step S12, the excitation device 66 irradiates the first page of the valuable document in the transport path 36 in the detection area 60, i.e. H. the document of value 12 from its back 75.

When the document of value 12 is irradiated from the first side, i.e. the back 75 in the example, with excitation radiation 67 from the excitation device 66, part of the excitation radiation 67 enters the document of value 12, in particular its substrate 70. Since the substrate 70 is at least partially transparent to the excitation radiation 67, part of the excitation radiation reaches the front side 72 of the substrate 70 or document of value 12, where it excites the luminescent substance 73. The luminescent substance then emits luminescent radiation with its characteristic properties, part of which passes through the substrate 70, which is at least partially transparent to the luminescent radiation, to the back 75 of the document of value 12 and emerges from it.

In step S14, the detection device 68 detects the luminescence radiation 69 emanating from the document of value, more precisely its back, forming detection signals which are fed to the evaluation device 64.

In step S16, the evaluation device 64 checks the value document depending on at least one property of the detected luminescence radiation 69. From the detection signals of the detection device 68, it determines the strength of the luminescence radiation as a property and compares this with a predetermined reference value. In this embodiment The strength used is an average value of the strengths or detection signals that are recorded for a respective document of value. If the intensity is above the reference value, the detected luminescent radiation represents an indication of the presence of the luminescent substance on the front of the document of value. The evaluation device 64 then outputs an indication signal which indicates the found indication of the presence of the luminescent substance on the front 72 of the document of value and thus also represents the authenticity of the document of value, to the machine control and evaluation device 46. Otherwise, it emits an indication signal that indicates a lack of the luminescent substance on the front 72 and thus an indication of a counterfeit.

The machine control and evaluation device 46 determines a sorting class depending on the indication signal and the sensor data from the other sensors.

The reference value used in step S16 can be determined, for example, by examining one or more reference value documents of the specified value document type by carrying out steps S10, S12 and S14 for each of the reference value documents. During transport, the reference value documents are in a position in which the back faces the first side of the detection area or the excitation device.

A second exemplary embodiment differs from the first exemplary embodiment in that the valuable documents of the specified value document type are checked in any position, i.e. the front with the luminescent material or the back can be facing the first side. The Corresponding testing device 44, more precisely its evaluation device 64, and the machine control and evaluation device 46 do not differ in their design from those of the first exemplary embodiment, only the valuable documents in the input compartment 20 can be present in at least two layers, in which the front side for some valuable documents at the top and others facing down.

In step S10, the transport device transports the document of value through the detection area and past the excitation device. The document of value is in a position in which either the front of the document of value or the back of the document of value faces the first side of the detection area or the excitation device. As far as the value document processing device is concerned, step S10 does not differ from step S10 of the first exemplary embodiment.

However, when the document of value is irradiated with excitation radiation 67 in step S12, the following happens:
If the first side, i.e. the side of the document of value irradiated directly by the excitation device 66, is the back 75 of the document of value 12 (cf. Figures 3C and 3D ), at least part of the excitation radiation 67 enters the document of value 12, passes through the substrate 70 and then excites the luminescent substance 73 on the front side 72 of the substrate 70 or on the front side of the document of value 12 to luminescence. The luminescent substance 73 emits luminescent radiation, part of which passes through the substrate 70 to the back 75 of the document of value, i.e. its first side, and emerges from the document of value 12.

Is the first page of the document of value, i.e. the side facing the excitation device 66, but the front of the document of value (cf. Figures 3A and 3B ), the excitation radiation 67 hits the luminescent substance 73 on the front side 72 of the substrate 70 directly and stimulates it to luminescence. A portion of the luminescence radiation 69 excited in this way is emitted directly into the detection area 60.

Step S14 is unchanged: the luminescent radiation emitted by the document of value is detected by means of the detection device 68.

In step S16, the evaluation device 64 checks the document of value depending on at least one property of the detected luminescence radiation. As in the first exemplary embodiment, it determines the strength of the luminescent radiation as a property of the detection signals from the detection device 68 and compares this with a predetermined reference value. If the intensity is above the reference value, the detected luminescent radiation represents an indication of the presence of the luminescent substance on the front of the document of value, regardless of the position the document of value is in. The evaluation device 64 then sends a signal, which represents the found indication of the presence of the luminescent substance on the front of the document of value and thus also of the authenticity of the document of value, to the machine control and evaluation device 46. The reference value used in step S16 of the first exemplary embodiment is used as the reference value, since in the case that the luminescence is excited from the back of the document of value, the excitation radiation is weakened somewhat when it passes through the substrate and the excitation radiation from the weakened excitation radiation luminescence radiation generated is weakened slightly when passing through the substrate to the back, the resulting luminescence radiation emanating from the document of value is weaker than the luminescence radiation that emanates from the document of value when the front side is directly irradiated.

Otherwise, it emits an indication signal that represents a lack of the luminescent substance on the front 72 and thus an indication that the document of value is counterfeit.

A third exemplary embodiment (cf. Fig. 5 ) differs from the second exemplary embodiment in that step S16 'is changed compared to step S16, but steps S10, S12 and S14 are unchanged. When checking, the position of the document of value 12 is taken into account during the detection of the luminescent radiation. More specifically, it is checked whether the detected luminescent radiation is an indication of the presence of the luminescent substance on the front 72 of the document of value 12. The corresponding testing device 44, more precisely its evaluation device 64, and the machine control and evaluation device 46 differ in their design from those of the second exemplary embodiment only in their programming or training for carrying out step S16 'and the further use of the results of step S16'.

For step S16', a first test criterion is now specified for layers in which the first side facing the excitation device 66 is the front side 75, and the luminescent substance 73 is directly illuminated by the excitation device 66 with excitation radiation 67, and for layers in which the back 75 is irradiated with excitation radiation 67 and the luminescent substance on the front side 72 is indirectly irradiated by the excitation radiation transmitted from the substrate 70, a second test criterion is specified.

In this exemplary embodiment, the two test criteria are structurally the same but use different parameter values. Simple threshold criteria are used, which, however, must be checked in the correct, specified order. It is checked whether the strength of the detected luminescence radiation is above a first or second reference value.

Since the detected luminescent radiation is stronger in the case of direct irradiation of the luminescent substance 73 on the front of the document of value than in the case of indirect illumination through the substrate 70, the first reference value is chosen to be larger than the second reference value. The first reference value can be obtained, for example, with the device used for testing by detecting luminescence radiation intensities in the different layers for one or more predetermined reference value documents of the value document type, the detection conditions essentially corresponding to those during the test. The first reference value can be chosen, for example, between the average value of the luminescence radiation intensities during direct irradiation with excitation radiation and the average value of the luminescence radiation intensities during indirect irradiation.

The second reference value can be slightly smaller than the average of the luminescence radiation intensities for indirect irradiation.

The sub-steps of step S16' are in Fig. 6 shown roughly schematically. When testing, in step S16' the first test criterion is checked in a first sub-step S16'.1 as to whether the strength of the detected luminescence radiation is above the first reference value. If this is the case, an indication of the presence of the luminescent substance is recognized on the front of the document of value, the front being the first page of the document of value. If this is not the case, the second test criterion is checked in substep S16'.2. More specifically, it is checked whether the strength of the detected luminescence radiation is above the second reference value. If this is the case, an indication of the presence of the luminescent substance on the front of the document of value is recognized, but the front is the second side of the document of value that is not directly irradiated with excitation radiation.

Otherwise it is recognized that there is no or not enough luminescent substance on the front of the document of value.

Two signals are then emitted in substep S16'.3, the first of which represents whether the luminescent substance is present on the front of the document of value or not, and the second whether the front is the first or the second page if it is present.

Alternatively, only one signal needs to be emitted that represents the three results found, for example by the amplitude of the signal.

The machine control and evaluation device 46 of the value document processing device 10 is designed to receive these signals and to compare the information about the position with information about the position of the document of value, which can be obtained by means of another sensor, in the example of the remission sensor 40, which captures an image of the document of value 12. This results in increased security of the test.

A fourth exemplary embodiment differs from the second exemplary embodiment in that step S16" is changed compared to step S16', but steps S10 to S14 are unchanged. In particular, valuable documents can be present in any position in the input compartment and can then be checked during transport When checking, the position of the document of value is taken into account when the luminescent radiation is detected.

For step S16" a first test criterion is now used for layers in which the front is directly illuminated by the excitation device with excitation radiation and for layers in which the back is irradiated with excitation radiation and the luminescent substance on the front is irradiated by the excitation radiation that has penetrated through the substrate is irradiated indirectly, a second test criterion is specified.

In this exemplary embodiment, the two test criteria are again structurally the same, but use different parameter values. Both criteria check whether the strength of the detected luminescence radiation is within the first or second reference intervals.

The limits of the reference intervals can be obtained analogously to the third exemplary embodiment by examining one or more reference value documents in different positions. For example, a respective interval can be set as the interval in which a predetermined proportion of the detected luminescence radiation intensities or all luminescence radiation intensities is or are located. The reference intervals are chosen so that they do not overlap.

When checking in step S16", the order in which the test criteria are checked is not important. It is checked in each case whether the strength of the detected luminescent radiation is within the respective reference interval. If this is the case, an indication of the presence of the luminescent substance is displayed the front of the document of value is recognized, whereby the position of the front results from the test criterion that was met.

If the intensity of the detected luminescent radiation is not within one of the two reference intervals, it is recognized that there is no or an incorrect amount of luminescent substance on the front of the document of value.

The test as to whether the intensity of the detected luminescence radiation lies within predetermined intervals is significantly stricter than a test with threshold criteria and is therefore more precise.

Two signals are then emitted, the first of which represents whether the luminescent substance is present on the front of the document of value or not, and the second whether the front is the first or the second page if it is present.

Alternatively, only one signal needs to be emitted that represents the three results found, for example by the amplitude of the signal.

The machine control and evaluation device 46 of the valuable document processing device 10 is designed to receive these signals and to compare the information about the position with information about the position of the valuable document, which is generated by means of another sensor, in the example of the remission sensor 40, which produces an image of the valuable document can be recorded and preserved. This results in increased security of the test.

A fifth exemplary embodiment in Fig. 7 differs from the third and fourth exemplary embodiments in that before checking the document of value, a position of the document of value 12 transported past the sensor device 62 is determined by means of another sensor, in the example of the remission sensor 40, on the basis of the detected properties of the luminescent radiation. The testing of the luminescence property in the evaluation device 64 then also takes place depending on the position information determined. The testing device 44 differs from the testing device of the third or fourth exemplary embodiment only in that the evaluation device 64 is replaced by a modified evaluation device 64". The latter is designed to receive the position signal from the machine control and evaluation device 46 and from the evaluation device Steps to be carried out in the following exemplary embodiment. All other components are unchanged, and the comments on these also apply here accordingly.

In the example, an image is used to determine the position, which is captured by the remission sensor 40 while the document of value is being transported past and, in the example, is evaluated by the machine control and evaluation device 46. The machine control and evaluation device 46 generates a position signal that represents the position of the document of value in the transport path and transmits this to the testing device 44, more precisely its evaluation device 64.

In the method, step S10 is unchanged from step 10 of the third and fourth exemplary embodiments.

At least partially parallel to this step, an image of the document of value is captured in step S11 by means of a sensor, in the example the remission sensor 40. A position of the document of value is determined from the image and a position signal representing the position is formed, which in the example is carried out by the machine control and evaluation device 46. The position signal is transmitted to the testing device 44, more precisely the evaluation device 64 or its interface to the machine control and evaluation device 46, which detects the position signal.

Steps S12 and S14 are unchanged from steps S12 and S14 of the third and fourth embodiments.

Step S16 ⁽⁵⁾ differs from step S16 'of the third exemplary embodiment or from step S16" of the fourth exemplary embodiment in that, depending on the received position signal, only that of the two test criteria is checked that is intended for the position determined by the Position signal is displayed.

This exemplary embodiment has the advantage that, on the one hand, the evaluation of the properties of the detected luminescence radiation is less complex and, on the other hand, the detected position information can also be used for other purposes can be used in the value document processing device 10. In addition, a more precise test is achieved, since it is impossible for an incorrectly dosed luminescent substance to just accidentally meet the test criterion that corresponds to the non-existent position of the document of value.

In other exemplary embodiments, as an alternative to or in combination with the intensity of luminescence radiation excited by means of the excitation radiation in the wavelength range specified by the detection device, a spectrum of the detected luminescence radiation can also be used, which includes intensities of the luminescence radiation in at least two narrow wavelength ranges.

In still other exemplary embodiments, as an alternative or in addition to the tests in the previously described embodiments, the spatial distribution of the luminescent substance on the document of value, which results from the spatial distribution of luminescent radiation, can be used as the sole or further property of the luminescent radiation.

The testing device is then designed to detect the luminescence radiation excited by the excitation device 66 in a spatially resolved manner and to generate corresponding luminescence images of the document of value 12 or at least of the security feature 74, which are evaluated in the evaluation device for checking the document of value 12. A luminescence image is understood to mean the representation of a spatial dependence of the property of the excited luminescence radiation.

In still other exemplary embodiments, a dynamic property, for example the onset and/or decay behavior of the luminescence, can also be used as a luminescence property during testing.

Still other exemplary embodiments can differ from the described exemplary embodiments in that the excitation device 66 is set up to emit excitation radiation 67 in the visible (VIS) spectral range and the detection device 68 is set up to detect radiation, in particular luminescent radiation 69, in the visible (VIS) spectral range . Value documents can then be checked with luminescent substances that can be stimulated to luminescence in the VIS.

Other exemplary embodiments differ from those described above in that documents of value can be checked which, instead of the polymer substrate, have a hybrid substrate with at least one polymer and one banknote paper layer or also a paper substrate.

Still other exemplary embodiments can differ from the previously described exemplary embodiments in that the sensor part 62 has a spectral sensor in which the excitation device 66 emits excitation radiation pulses in predetermined, in particular different, wavelength ranges in a predetermined time sequence and the detection device 68 emits possibly excited luminescence radiation for each of the pulses recorded spectrally resolved. Such a spectral sensor is in DE 10 2009 058 805 A1 described by the applicant, the contents of which are hereby incorporated by reference into the description. When testing, the spectrum recorded can then be used as a property of the luminescent radiation the detected luminescence radiation, ie the strength of the luminescence radiation at predetermined wavelengths or in predetermined wavelength ranges can be used.

Still other exemplary embodiments may differ from the previously described exemplary embodiments in that the detection device 68 comprises a spectrometer. DE 10 2006 045 624 A1 The applicant describes a device in which the excitation device 66 and the detection device 68 are partially integrated. The content of the DE 10 2006 045 624 A1 is hereby incorporated by reference into the description. When testing, the detected spectrum of the detected luminescent radiation, ie the strength of the luminescent radiation at predetermined wavelengths or in predetermined wavelength ranges, can also be used here as a property of the luminescent radiation.

Figure 8 shows a further example of a testing device 80 for testing documents of value, which have a front side 72 and a back side 75 opposite the front side and which have a substrate 70 and a predetermined luminescent substance 73, preferably applied to the substrate 70 in at least a section of the front side of the document of value 12 include, that is, documents of value as tested in the previous exemplary embodiments. In the value document processing device 10, the checking device 44 is replaced by the checking device 80, which only differs from the checking device 44 in that a reflection device 82 is now provided. All other components of the device with the exception of the evaluation device 64, which is provided by a Evaluation device 84 is replaced, are unchanged, so that the same reference numbers are used for them and the explanations for these in the previous exemplary embodiments also apply here.

The reflection device 82 is designed and arranged in such a way that it reflects optical radiation coming from the detection area 60 into the detection area 60, so that when a document of value 12 is present in the detection area 60, it at least partially impinges on the document of value 12 and at least partially enters it.

In the example, the reflection device 82 reflects both excitation radiation 67 ^T coming from the detection area 60 and luminescence radiation of the luminescent substance 73 generated by the excitation radiation, which is emitted into the detection area 60 but not the substrate 70.

The excitation of luminescence occurs, especially if the document of value has an in Fig. 9A illustrated the situation in Fig. 3C or 3D appropriate position, with fewer losses. In Figures 9A and 9B Various excitation and reflection processes are shown side by side for the sake of clarity; the slanted incidence only serves to make the illustration clearer.

If the excitation radiation 67 passes through the substrate 70 to the luminescent substance 73, this is stimulated to luminescence by a portion 67.1. The resulting luminescence radiation is partly emitted into the substrate (69.1) and partly into the detection area 60 (69.2). The part 69.1 of the luminescent radiation emitted into the substrate at least penetrates partially the substrate 70 and is released on the first side or on the back 75. The part 69.2 of the luminescent radiation emitted into the detection area 60 would be lost without the reflection device 82, but in the example it is reflected back onto the document of value 12, passes through it at least partially to the first side, the back, and can then start from the document of value be detected by the detection device.

Furthermore, part 67.2 of the excitation radiation, which has passed through the substrate but has not excited any luminescent radiation, emerges from the document of value and passes through the detection area 60 to the reflection device 82. This reflects this part 67.2 of the excitation radiation at least partially back onto the document of value, where it hits the luminescent material 73 on the front 72. The luminescent substance 73 is in turn excited to luminescence. The luminescence radiation 69.3 excited by the reflected excitation radiation 67.2 is partially emitted into the substrate and, after transmission through the substrate 70, can be detected from the document of value by means of the detection device 66. Another part 69.4 of the luminescent radiation excited by the reflected excitation radiation 67.3 is emitted into the detection area 60, reaches the reflection device 82 and is reflected by it back onto the document of value. The reflected luminescence radiation 69.4 at least partially penetrates the document of value. It then emanates from the back of the document of value and can be detected by means of the detection device 66.

Overall, the detection device 66 detects four contributions of luminescent radiation in the first order: the non-reflected part 69.1 generated directly by the excitation radiation 67.1, the reflected part 69.2 generated directly by the excitation radiation 67.1, the non-reflected part generated by the reflected excitation radiation 67.2 69.3 and the reflected part 69.4 generated by the reflected excitation radiation 67.2. These parts cannot be separated, but are detected together as luminescent radiation 69 generated by the excitation radiation. In contrast, in a test facility without a reflector according to Fig. 2 only the luminescence corresponding to the proportion 69.1 can be detected.

The excitation of luminescence occurs when the document of value has an in Fig. 9B illustrated the situation in Fig. 3A or Fig. 3B corresponding position, also with fewer losses:
If the excitation radiation 67 reaches the front side 75 and thus the luminescent substance 73 directly, this is stimulated to luminescence by a portion 67.1. The resulting luminescence radiation is partly emitted into the substrate (69.1) and partly into the detection area 60 (69.2). The part 69.1 of the luminescent radiation emitted into the substrate at least partially penetrates the substrate 70, is reflected by the reflection device 82, passes through the document of value 12 again and is emitted on the first side or on the front side 72. The part 69.2 of the luminescent radiation emitted into the detection area 60 on the first side can be detected directly by the detection device 68 as part of the luminescence radiation emanating from the document of value.

Furthermore, a part 67.2 of the excitation radiation, which has not excited any luminescence on the front of the document of value, passes through the substrate 70 and is reflected back onto the document of value by the reflection device 82. This portion 67.3 traverses the substrate 70 and hits the luminescent substance 73 on the front side 75. The luminescent substance 73 is in turn excited to luminescence. The luminescence radiation 69.3 excited by the reflected excitation radiation 67.3 is partially emitted into the substrate and, after transmission through the substrate 70, reflection at the reflection device 82 and renewed transmission through the document of value, can be detected as emanating from the document of value by means of the detection device 68. Another part 69.4, the luminescence radiation excited by the reflected excitation radiation 67.3, is emitted directly into the detection area 60 and can be detected by means of the detection device 68.

Overall, the detection device 68 detects four contributions of luminescent radiation in the first order: the non-reflected part 69.2 generated directly by the excitation radiation 67.1, the reflected part 69.1 generated directly by the excitation radiation 67.1, the reflected part generated by the transmitted, reflected excitation radiation 67.3 Part 69.3 and the non-reflected part 69.4 generated by the reflected excitation radiation 67.3. These parts cannot be separated, but are detected as luminescent radiation 69 generated by the excitation radiation. In contrast, in a test facility without a reflector according to Fig. 2 only the proportion 69.2 corresponding luminescence can be detected.

In this way, for a given intensity of the excitation radiation, luminescence radiation is detected, which is significantly stronger than without the reflection device 82.

The exemplary embodiments of the test method already described can be carried out accordingly with the test device 80, although during and/or after step S12 and before or during step S14, a step S13 of reflecting excitation emanating from the document of value on the second page is carried out. and luminescent radiation is carried back onto the document of value.

The distance between the transport path and the reflection device 82 is between 8 and 12 mm in the example, more precisely about 10 mm. In other exemplary embodiments, larger or smaller distances can also be provided.

The reflection device 82 preferably has a high reflectivity or a high reflectivity, in the example of more than 95%, for both excitation and luminescence radiation, in order to be able to utilize both of the above-mentioned mechanisms of action.

The embodiments of the reflection device 82 according to the invention shown below in the Fig. 10 to 17 are characterized in that the reflection device is designed in such a way that it focuses the reflected excitation and/or luminescence radiation into the detection area. A focal plane or focal point of the reflection device lies less than 2 mm, preferably less than 1.5 mm, above and less than 2 mm, preferably less than 1.5 mm, below a transport plane along which the documents of value are transported on the transport path 16 become. When reflected, the excitation and/or luminescence radiation is then at least approximately focused on the transported documents of value. By focusing, the reflected excitation radiation can at least approximately stimulate more luminescence radiation in the detection area and thus on the document of value therein, which can also be detected by the detection device. The luminescence radiation that is at least approximately focused in the detection area and thus in the document of value can also be better detected, since the detection device is designed in such a way that it can detect luminescence radiation coming from the detection area. Without such focusing, reflected components may not be detected by the detection device, depending on the direction of propagation.

Figure 10 shows a further embodiment of the reflection device 82 in a schematic side view. The reflection device 82 has a cylindrical hollow mirror 83, which is shown in cross section here and is preferably positioned so that the radius of curvature of the cylindrical surface is approximately in the middle of the detection area 60 or the measuring plane of the sensor part 62 and / or in the plane of the substrate 70 or document of value 12 lies in the transport path. The scattered excitation radiation and/or the luminescence radiation that arises near the focal line is reflected back approximately into the focal line by the cylindrical hollow mirror 83, as illustrated by the arrowed rays. Optionally, a transparent protective pane made of glass, sapphire, or similar can be attached between the transport level of the valuable documents and the reflection device.

Figure 11 shows a further embodiment of the reflection device 82 in a schematic side view. Instead of the cylindrical hollow mirror 83, the reflection device 82 has a reflectively coated cylindrical lens 84, which is shown in cross section here and whose convexly curved side 84 'is reflectively coated. Analogous to that in Fig. 10 In the example shown, the scattered excitation radiation and/or the luminescence radiation that arises in the vicinity of the focal line is also reflected back approximately into the focal line. The advantage of this embodiment is that there is a flat surface 84" on the banknote transport level, which is robust against banknote abrasion, reduces the risk of a transport jam and can be easily cleaned.

Figure 12 shows yet another embodiment of the reflection device 82 in a schematic side view. In contrast to the in Fig. 10 In the example shown, instead of a cylindrical hollow mirror 83, the reflection device 82 has a Fresnel cylindrical hollow mirror 85, which has a plurality of cylindrical surfaces 85 ', 85" with different radii, which are positioned so that a common focal line results, which is approximately in the middle of the detection area 60 or in the measuring plane of the sensor part 62 or in the transport plane of the valuable document 12. The scattered excitation radiation and / or the luminescence radiation that arises near the focal line is reflected by the mirror surfaces 85 ', 85 "in a significantly larger angular range reflected back into the focal line than with a simple cylindrical concave mirror. Optionally, a transparent protective pane made of glass, sapphire, or similar can be attached between the transport level of the valuable documents and the reflection device.

Figure 13 shows yet another embodiment of the reflection device 82 in a schematic side view. The reflection device 82 here has a Fresnel cylindrical lens 86, the curved surfaces 86 ', 86" of which are reflectively coated. Analogous to that in Fig. 12 In the example shown, in this embodiment several convex cylindrical lens surfaces 86', 86" with different radii are combined or arranged in such a way that a Fresnel cylindrical lens with a single focal line is created, and the curved sides are coated with a reflective coating. The advantage of this embodiment is in particular that A flat surface of 86" is created in relation to the banknote transport plane, which is robust against banknote abrasion and can be easily cleaned. The Fresnel arrangement allows larger angular areas to be reflected back than with a simple cylindrical lens.

Figure 14 shows a special design of edge regions of the reflection device 82 in Fig. 10 in a cross-sectional view perpendicular to the Transport direction. In the example shown, the upper and lower ends of the reflecting surface (outer surface) of the cylindrical hollow mirror 83 (cf. Fig. 10 ) each has a spherically or aspherically curved section 83a, through which the edge drop of the cylinder reflection is reduced and / or compensated for by at least part of the excitation and / or luminescence radiation emanating from the document of value 12 in the direction of the ends of the cylinder hollow mirror 83 being returned to the document of value 12 is reflected, as indicated by the two outer arrows. This ensures that an increase in the detectable luminescence intensity or luminescence radiation intensity is also achieved on the outermost or uppermost and lowermost tracks of the sensor part (not shown). A corresponding design of the edge areas is also required for reflection devices Fig. 11, Fig. 12 and Fig. 13 possible.

Figure 15 shows a second example of a special design of edge regions of the reflection device 82 in Fig. 10 in a cross-sectional view perpendicular to the transport direction. In the example shown, the upper and lower ends of the reflecting surface (outer surface) of a cylindrical hollow mirror 83 (cf. Fig. 10 ) each has a plane mirror 83b. The plane mirrors 83b reflect at least part of the light emanating from the edge regions of the document of value 12, which would be reflected by the cylindrical hollow mirror 83 into an area that lies outside the detection range 60 and/or the measuring range of the sensor part (not shown), back into the measuring range - this light is, so to speak, "folded back", as is clear from the outer solid arrows compared to the dashed arrows - which reduces any possible edge fall-off. Compared to concave ends, plane mirrors are easier to manufacture and therefore more cost-effective. A corresponding The design of the edge areas is also appropriate for reflection devices Fig. 11, Fig. 12 and Fig. 13 possible.

Figure 16 shows another example of an embodiment of a reflection device 82 with several spherical mirrors 87 for several tracks. Such a reflection device 82 is used in particular when the illumination of the document of value to be checked is not (at least approximately) line illumination, but rather individual tracks with clear distances between them. In such applications, the excitation and/or luminescent light emanating from the document of value 12 is efficiently reflected towards the document of value using a single spherical mirror 87 per track.

This can be done, as in the example shown, using spherical concave mirrors or, analogously to that in Fig. 11 Example shown can be achieved using plano-convex lenses that are mirrored on the curved side. Analogous to the above in connection with Figures 12 and 13 In the variants described, Fresnel mirrors or lenses can also be used to increase the angular ranges.

Figure 17 shows yet another embodiment of the reflection device 82 in a schematic side view. This is a variant of the reflection device in Fig. 11 . In the example shown, the cylindrical mirror surface 84 'of the reflectively coated cylindrical lens 84 is at a finite distance d, preferably between 1 and 20 mm, opposite the transport direction with respect to the illumination optics 87a of the excitation device 66 (not shown) offset. This causes the reflected excitation radiation to be offset by twice the amount. The luminescence radiation excited by this mirrored excitation radiation can contribute to the detected or detectable luminescence radiation for a longer time, since the document of value 12 must be transported further together with the security feature 74 located thereon until the security feature 74 has left the detection area 60 of the detection device 68.

In addition to a further improved increase in the intensity of the detectable luminescence radiation on fast-running banknote processing machines (e.g. >3m/s, >5m/s, >7m/s), this arrangement with an offset increases the selectivity with which slow and fast decay time constants of luminescence can be distinguished.

As an alternative to the offset d, the (cylindrical) mirror 84 'can also be tilted in its alignment with the perpendicular L of the transport plane.

The above statements regarding the coated cylindrical lens 84 also apply correspondingly to a reflection device 82 with a hollow cylindrical mirror 83 (cf. Fig. 10 ), Fresnel cylindrical concave mirror (cf. Fig. 12 ), coated Fresnel cylindrical lens (cf. Fig. 13 ) or their spherical variants (cf. Fig. 16 ).

The above in connection with the Figures 10 to 16 The advantageous effects of the reflection device 82 described can also be achieved if the reflection device 82 has a retroreflector or is designed as a retroreflector.

The devices and methods described are particularly suitable for testing luminescence features with IR excitation and IR emission, i.e. in the wavelength range from 750 to 2,500 nm, preferably from 800 to 2,100 nm.

Claims (17)

1. Method for checking documents of value (12) which have a front side (72) and, opposite the front side (72), a rear side (75) and comprise a substrate (70) and, applied on the substrate (70) in at least one section of the front side (72) of the document of value (12), a specified luminescent substance, the method comprising the steps of:

   - irradiating a first side of the document of value (12) with excitation radiation (67) by means of an excitation device (66) to excite luminescence of the luminescent substance, wherein the first side is the rear side (75) of the document of value (75),

   - reflecting a part of the excitation radiation (67) that emerged on the front side (72) of the document of value (12) after transmission through the document of value (12), at least partially back to the document of value (12), and exciting the luminescent substance to emit luminescence radiation (69) by way of the reflected part, and/or reflecting luminescence radiation (69) which was generated by excitation of the luminescent substance on the front side (72) of the document of value (12) by means of the excitation radiation (67) and is emitted on the front side (72) of the document of value (12), at least partially back to the document of value (12), wherein upon reflection the excitation radiation and/or luminescence radiation (67 or 69) is at least approximately focused at the document of value (12),

   - capturing luminescence radiation (69) which was excited by excitation of the luminescent substance on the front side (72) of the document of value (12) by way of at least one part of the excitation radiation (67) after transmission through the substrate (70) of the document of value (12) and emerges from the document of value (12) at least partially after transmission through the document of value (12) at the rear side (75) of the document of value (12), by means of a capturing device (68),
   wherein during capturing also at least one part of the luminescence radiation (69) excited by the reflected part of the excitation radiation (67) is likewise captured after transmission to the rear side (75) of the document of value (12) and emergence from the document of value (12), and/or during capturing the reflected luminescence radiation (69) is likewise captured at least partially after transmission to the rear side (75) of the document of value (12) and emergence from the document of value (12), and

   - checking the document of value (12) in dependence on at least one property of the captured luminescence radiation (69) by means of an evaluation device (64).
2. Method according to Claim 1, wherein during the check a check is performed as to whether the captured luminescence radiation (69) constitutes an indication of the presence of the luminescent substance on the front side (72) of the document of value (12).
3. Method according to Claim 1 or Claim 2, wherein the excitation radiation (67) is reflected with a reflectance of more than 90°.
4. Method according to any of the preceding claims, wherein the luminescence radiation (69) is reflected with a reflectance of more than 90%.
5. Method for checking documents of value (12), which have a front side (72) and, opposite the front side (72), a rear side (75) and comprise a substrate (70) and, applied on the substrate (70) in at least one section of the front side (72) of the document of value (12), a specified luminescent substance, the method comprising the steps of:

   - transporting the documents of value (12) individually past an excitation device (66), which is configured to emit excitation radiation (67) to excite luminescence of the luminescent substance,

   - meanwhile irradiating at least a section of a first side of a respective document of value (12) with excitation radiation (67) by means of the excitation device (66),

   - reflecting a part of the excitation radiation (67) that emerged on a second side, opposite the first side, of the document of value (12) after transmission through the document of value (12), at least partially back to the document of value (12), and exciting the luminescent substance to emit luminescence radiation (69) by way of the reflected part, and/or reflecting luminescence radiation (69) which was generated by excitation of the luminescent substance on the front side (72) of the document of value (12) by means of the excitation radiation (67) and exits from a second side, opposite the first side, of the document of value (12), at least partially back to the document of value (12),
   wherein upon reflection the excitation radiation and/or luminescence radiation (67 or 69) is at least approximately focused at the transported documents of value (12),

   - capturing at least one part of luminescence radiation (69) which exits from the first side of the document of value (12) and which, if the first side is the front side (72) of the document of value (12), is generated by excitation of the luminescent substance of the document of value (12) and was emitted by the document of value (12), or which, if the first side is the rear side (75) of the document of value (12), was excited by excitation of the luminescent substance of the document of value (12) by way of at least one part of the excitation radiation (67) after transmission through the substrate (70) of the document of value (12) and emerges at least partially after transmission through the substrate (70) at the first side, by means of a capturing device (68), wherein during capturing at least one part of the luminescence radiation (69) excited by the reflected part of the excitation radiation (67) which exits from the first side of the document of value (12) is likewise captured, and/or during capturing the reflected luminescence radiation (69) is likewise captured at least partially after transmission to the first side of the document of value (12) and emergence from the document of value (12) on the first side, and

   - checking the document of value (12) in dependence on at least one property of the captured luminescence radiation (69) by means of an evaluation device (66).
6. Method according to Claim 5, wherein the excitation radiation (67) is reflected with a reflectance of more than 90%.
7. Method according to Claim 5 or Claim 6, wherein the luminescence radiation (69) is reflected with a reflectance of more than 90%.
8. Method according to any of Claims 5 to 7, wherein during the check a check is performed as to whether the captured luminescence radiation (69) constitutes an indication of the presence of the luminescent substance on the front side (72) of the document of value (12).
9. Method according to any of Claims 5 to 8, wherein the check is performed such that the result of the check is independent of whether the first side of the document of value (12) is the front side (72) of the document of value or the rear side (75).
10. Method according to Claim 9, wherein during the check an intensity of the captured luminescence radiation (69) is compared with a reference value that is dependent of whether or not the front side (72) is the first side.
11. Method according to any of Claims 5 to 8, wherein during the check at least two check criteria are used, of which a first check criterion is a criterion of the first side being the front side (72) of the document of value, and the second check criterion is a criterion of the first side being the rear side (75) of the document of value.
12. Method according to Claim 11, wherein during the check it is also ascertained whether the first side is the front side (70) or the rear side (75).
13. Method according to any of Claims 5 to 8, which furthermore comprises:

    capturing a pose of the document of value (12), with the pose indicating whether the first side of the document of value (12) is the front side (72) or the rear side (75), and

    wherein the check is carried out in dependence on the captured pose of the document of value (12).
14. Method according to any of the preceding claims, wherein a document of value (12) whose substrate (70) is a polymer substrate is checked.
15. Apparatus (44) for checking documents of value (12) which have a front side (72) and, opposite the front side (72), a rear side (75) and comprise a substrate (70) and, applied on the substrate (70) in at least one section of the front side (72) of the document of value, a specified luminescent substance (73), in a capture region (60) of the apparatus having

    - an excitation device (66) for irradiating a first side of an individual one of the documents of value (12) in the capture region (60) from a first side of the capture region (60) to excite the luminescent substance to emit luminescence radiation (69),

    - a reflection device (82) which reflects back excitation radiation (67) that exits from a second side of the document of value (12), opposite the first side, and/or luminescence radiation (69) that exits from a second side of the document of value (12), opposite the first side, and which is configured such that it focuses the reflected excitation radiation and/or luminescence radiation (67 or 69) into the capture region (68),

    - a capture device (68) for capturing luminescence radiation (69) which is excited by means of the excitation radiation (67) and exits from the first side (72) of the document of value (12) in the capture region (60) in the direction of the first side of the capture region (60), and

    - an evaluation device (64) for checking the document of value (12) in dependence on at least one property of the captured luminescence radiation (69),

    wherein the excitation device (66), the capture device (68) and the evaluation device (64) are configured to carry out a method according to any of Claims 1 to 14.
16. Apparatus according to Claim 15, wherein the evaluation device (64) has an interface by means of which at least one signal indicating the pose of the document of value (12) is capturable and wherein the evaluation device (64) is configured to carry out the check according to Claim 12.
17. Apparatus (10) for processing documents of value (12), which have a front side and, opposite the front side, a rear side and comprise a substrate (70) and, applied on the substrate (70) in at least one section of the front side of the document of value (12), a specified luminescent substance, having

    - a feed device (14) for documents of value (12) to be processed, into which documents of value (12) can be introduced and individually output thereby,

    - an output device (16), in which processed documents of value (12) can be placed,

    - a transport device (18) for the individual transport of documents of value (12) from the feed device (14) along a transport path (36) to the output device (16),

    - a control device (46) for controlling the transport device and/or output device (18 or 16), and

    - an apparatus for checking documents of value according to either of Claims 15 and 16,

    wherein the apparatus for checking and the transport device (18) are configured and arranged such that the transport path (36) passes through the capture region of the apparatus for checking, and

    wherein the control device (46) is connected to the apparatus for checking via a signal connection and is configured to control the transport device (18) an/or the output device (16) depending on results from the apparatus for checking.

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