JPH1186072A - Paper money authentication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device which automatically authenticates paper money. SOLUTION: The paper money authentication device for bank motes 1 uses bar codes printed on the surfaces of the bank notes 1 with fluorescent ink. The bar codes are read out by conveying the paper money through a read station 4, where a ultraviolet-ray lamp 5 lights up the paper money 1 to make information in bar code form printed on the paper money fluoresce and a photodiode 9 sensing the wavelength of the fluorescence detects it. An additional read station may be provided so as to surely read the codes regardless of the direction where the paper money are conveyed and which edge of each paper money comes first. The output of the photodiode can be supplied to a neural network so as to support a read of an old and dirty paper money in addition to the detection of a forged paper money.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bill validating apparatus for automatically validating bank bills and similar sheets.

[0002]

2. Description of the Related Art After a customer verification procedure, an automatic cash dispenser (hereinafter referred to as "AT") which pays out bank notes to bank customers
M ”) is used worldwide. Such machines can not only pay out banknotes, but also receive, authenticate and verify banknotes, and consequently accept banknotes supplied by bank customers and recycle them. It is also desirable to be adapted to be able to.

[0003] As a premise for such authentication, banknotes must contain information in a machine-readable form. To this end, three banks that issue Scottish banknotes have already introduced a common type of code marking on banknotes using well-known barcode symbols.

[0004] These markings encode the face value of the banknotes and information identifying the issuing bank. The marking is invisible with ordinary light, but is printed with fluorescent ink that fluoresces with ultraviolet light.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus for automatically authenticating banknotes and similar sheets.

[0006]

SUMMARY OF THE INVENTION According to the present invention, an apparatus for automatically authenticating banknotes comprises a banknote transport means for transporting such banknotes that pass through a reading station one after the other, and a radiating means. A radiation beam generator means for generating light rays and emitting such generated radiation rays onto the bill as the bills pass successively through the reading station; and a machine-readable encoding on the bill. Electronic reading means for reading information responsive to such radiation.

[0007] The radiation beam generator means is arranged to emit a radiation beam as each bill passes the reading station, and the electronic reading means is arranged to receive radiation rays emanating from such bills. ,
Preferably, the carrying means is configured such that the bill passes between the radiation beam generator means and the electronic reading means.

In practicing the present invention, the electronic reading means can sense different predetermined wavelengths of light to the generated radiation, such that the generated radiation is in the ultraviolet region of the radiation spectrum. Can be The predetermined wavelength is a radiation wavelength of the fluorescent ink, and a code marking is printed on a bill to be read out using the ink, and the fluorescent ink can be made to feel ultraviolet light.

[0009] The bill to be read is actually rectangular and has a pair of longer edges and a pair of shorter edges, the transport means being provided with any one of the predetermined pair of edges being the leading edge. It is preferable that the banknotes are adapted to be aligned.

In an embodiment of the present invention, a plurality of reading stations are provided, regardless of which side of the bill is facing up, and which edge of a given pair is the leading edge. Regardless of whether or not the information is encoded, it is preferable that the encoded information can be read.

In an embodiment of the present invention, a learning system is used that distinguishes bank notes and similar notes from information encoded on the notes that can be read by the reading means. learn. This has the advantage of reducing the algorithm complexity required to reduce the authentication time.

For a better understanding of the present invention, reference is made to the accompanying drawings.

[0013]

DETAILED DESCRIPTION OF THE INVENTION Referring now to FIG. 1, there is shown in schematic form, a representative banknote surface 1 as issued by a banknote issuing bank in Scotland. Common types of readable information printed on the note, such as the name of the issuing bank, the denomination or denomination and security of the note, as well as encoded information, may be Printed with ink that is invisible to the eyes that fluoresce below. The wavelength of the fluorescence has a peak at 530 nm in the green region of visible light. The encoded information is printed in the form of a 13-element barcode, and the dimensions of each bar are 2 mm x 26 mm. The code overlaps in two regions 2 and 3.
The two regions 2 and 3 are located relatively to a center line parallel to the shorter and longer edges, respectively.
Whether the leading edge of the bill is the shorter edge or the longer edge, the code is arranged so that the code can be read equally well. Each bar is either "1" (green fluorescence) or "0" (no fluorescence).

[0014] Regardless of the issuing bank, the first two elements of the encoded information are 1,0 and the last two are 0,
It is one. The nine middle elements represent different banks and different denominations. Table 1 below shows codes for various issuing banks and denominations.

Table 1 Issued Bank Denomination Class Code Bank of Christesdale 10 £ 1010001000101 Bank of Christesdale 10 £ 1011010110101 Bank of Christesdale 20 £ 1000101010001 Bank of Scotland 5 £ 1001011001101 Bank of Scotland 10 £ 1010010100101 Bank of Scotland 20 £ 1011011000101 Royal Bank of Scotland £ 5 1011011111001 Royal Bank of Scotland £ 10 1000010010001 Royal Bank of Scotland £ 20 1011101011101 Encoding printed on bank note as shown in FIG. A reading station 4 for reading the obtained information is shown in FIGS. The reading station 4 includes an ultraviolet tube 5 arranged to emit ultraviolet light while the banknote 1 is transported through the reading station by a suitable transport means.
One example of a suitable transport means is described below and is shown in FIGS. The transport means moves the banknotes with the longer edge as the leading edge, and the width of the tube 5 is large enough to ensure that the banknotes emit ultraviolet light over the full width of the banknote as it passes through the reading station. is there. The marking on the fluorescent ink on the banknote 1 emits light. And as described above with reference to FIG. 1, the marking of the barcode on the Scottish banknote is approximately 5
Emit green light with a peak at 30 nm.

An electronic reading means 6 is provided at the reading station 4 for detecting such light emanating from bar code markings on the banknote 1. The reading means 6 is arranged on the opposite side of the banknote from the reading station 4 to the tube 5 and directly above the tube 5.
An enlarged view of the reading means 6 is shown in FIG. The reading means 6 comprises a plate 7 in which there is a housing 8 containing a selected photodiode 9 with a peak response near 500 nm close to the peak frequency of the emission of fluorescence from the banknote 1. The housing 8 includes a 1 mm wide slot 10 through which light from the banknote 1 reaches the photodiode 9. In order to improve the signal-to-noise ratio of the signal detected by the photodiode 9, an interference filter 13 (shown diagrammatically in FIG. 3) is provided before the photodiode and reaches the diode 9. Reduces the level of infrared and low blue signals.

When the longer edge is at the reading station, which is the leading edge, there are four possible orientations of the bill and, therefore, there are four possible locations for bar code information. For banknotes with the surface facing up, there are two possible locations. The reading means 6 is arranged on one of them. A second electronic reading means 11 similar to the reading means 6 is provided, which is parallel to the reading means 6 and reads the barcode when the barcode is in the second position. A second reading station is provided for the third and fourth possible positions of the barcode, which occurs when the banknotes are oriented in opposite directions, which is similar to the above, but opposite. It is arranged toward the direction. This is shown more clearly in FIG.

FIG. 3 shows a side view of two reading stations 4 and 4 'arranged to read a bar code on a bank note 1 with the long edge leading edge in all its possible orientations. ing. The reading station 4 comprises an ultraviolet lamp 5 behind a reflector 12. Reading means (reading means 6 in FIGS. 2 and 3) comprising a photodiode 9 and a filter 13 is provided towards the lamp 5. Still another reading means is located on the same straight line as the reading means 6, but is not visible in FIG. (A further reading means is shown in FIGS. 2 and 3 as reading means 11). The reading station 4 'is identical in all respects to the reading station 4, but with the surface in the opposite direction. It is arranged in the opposite orientation so that the barcode on the bank note passing through the device can be read. In this way, if the longer edge is the leading edge, it is possible to ensure that the bar code above it is read irrespective of the orientation of the banknote.
If the shorter edge is the leading edge, four more orientations are possible, requiring two more reading stations, each with two reading means.

The reading station 4 has one light source arranged on one side of the banknote 1 and reading means arranged on the opposite side of the banknote 1, and the banknote 1 passes between them. Described and illustrated. However, it is also possible to arrange both the light source and the reading means on the same side of the bill as it passes.

FIGS. 6 and 7 show the banknote transport means used to transport banknotes through the reading station. The transport means comprises four tension control type drive belts 21, 22, 23 and 24. The drive belts 21 and 22 are on the upper side of the bill passage, and the drive belts 23 and 24 are on the lower side. (Belt 24 is not visible in the figure) The upper belt 21 has shafts 28, 29 extending across the unit.
Pass over the wheels 25, 26 and 27 above. The lower belt 23 includes shafts 28, 29 and 30.
Wheel 3 on shaft (not shown) below
Pass over 1, 32 and 33. Upper belt 22
Is also on respective shafts 28, 29 and 30, but each shaft is a wheel 25, 26
And 27 over the wheel that is separated along the shaft. The lower belt 24 is the upper belt 2
2 and is the same as the lower belt 23, but laterally spaced therefrom. The various shafts are driven by gears that are connected through a drive train to a source of kinetic power (not shown). The shafts 29 and 32 are spring-loaded to maintain tension in the belt.

In using the above apparatus, the signal received from the photodiode at the reading station is serially divided into thirteen equal segments corresponding to thirteen digit bar codes printed on banknotes. ,
Each segment is digitized by being applied to a threshold unit. Signals above the threshold are digitized as "1" and signals below the threshold are digitized as "0". For a clean and valid note, this will be sufficient to provide a signal corresponding to one of the codes shown in Table 1 and to provide the respective denomination and issuing bank instructions. However, the device needs to respond to old, dirty banknotes. In such a case, "1" may be erased due to contamination or deterioration of fluorescence, and may be converted as "0". In addition to detecting counterfeit banknotes, the output signal from the reading means can be processed using a neural network to overcome this problem.

The neural network of the backpropagation architecture of the error is shown in FIG. It contains several nodes arranged in layers. In the example shown, the input layer 51, the intermediate layer 5
A three layer neural network including two and an output layer 53 is used. The number of nodes in the input layer corresponds to the number of inputs. (For explanation, input layer 5
In FIG. 1, four nodes are shown. In the example shown, two nodes are provided in the middle layer 52, but this number can be increased or decreased as needed. In the case of the output layer 53, the number of nodes corresponds to the number of different classes of output required. In FIG. 8,
The output layer 53 is provided with four nodes, but this is merely for convenience of explanation. For the nine possible banknotes listed in Table 1, if counterfeit banknotes have already been rejected, nine output nodes are required, and each banknote may be a fake bill. To deal with it, 18 output nodes are needed. In the neural network, connections are made from all input nodes to all hidden layer nodes, and connections are made from all hidden layer nodes to all output layer nodes. Each input connection to one node is weighted. Every node computes the sum of its weighted inputs. The calculated sum is compared against a predetermined threshold for the node. If the sum exceeds the threshold, the output of that node will be "1", otherwise it will be "0".

In order for a neural network to perform its function, it must be "taught".
One example of a limited operation network teaches to authenticate Scottish 20 pound banknotes issued by three issuing banks and to verify authenticated banknotes by distinguishing between real and counterfeit banknotes. Network. Therefore, there are six types of positive results, and therefore the output layer of the neural network requires six nodes. Further, no fluorescence can be detected, thus providing an additional "0" output. The required output codes from the output layer are shown in Table 2 below.

Table 2 Banknotes Status Output Court 20 Hours Bank Off Scotland Valid 100000 20 Hours Credit Bank Valid 010000 20 Hours Royal Bank Off Scotland Valid 001000 20 Hours Bank Off Scotland 100 Authentic Flott 000 Bank Counterfeit 000010 20 points Royal Bank of Scotland Counterfeit 000001 The number of input nodes in the above example was thirteen. Each input node then has a 1 into which the read signal is divided.
One of the three segments has been received. The input to each node corresponds to one of the digits of the code shown in Table 1 for that type of banknote, in the case of a signal fully read from a valid twenty pound banknote. The middle layer of four nodes was used as described above, and there were six output nodes.

For the learning process, the network was initially started with nodes with random weights and thresholds, and a known type of 20 pound bill supplied. If the output signal was incorrect, its weight was adjusted by the back propagation method, which was first the output node, and then the intermediate nodes were adjusted to reduce the error. This "learning" method of back propagation can be controlled by appropriate software. In practice, the barcodes of counterfeit banknotes are sufficiently different from real banknotes and can be distinguished by properly taught neural networks. However, if necessary, sensors can be added to detect parameters other than the fluorescence of the barcode and provided for false counterfeit detection.
Such a sensor can be located either before or after the barcode reading station.

[Brief description of the drawings]

FIG. 1 shows a representative bank note of the kind intended to be read by a device implementing the invention.

FIG. 2 shows a plan view of a reading station used in an apparatus embodying the present invention, respectively.

FIG. 3 shows a front view of an end of a reading station used in an apparatus embodying the present invention, respectively.

FIG. 4 shows an enlarged detail of FIG. 3;

FIG. 5 is a side view of the reading station presented in FIGS. 2 and 3;

FIG. 6 is a side view of the banknote transport mechanism.

FIG. 7 is a plan view of a banknote transport mechanism.

FIG. 8 illustrates a neural network used in an embodiment of the present invention.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Seek Mylan Scotland DD2 2LP Dundee Eason's Angle 7

Claims (1)

[Claims] 1. A device for automatically authenticating banknotes and similar sheets and the like, comprising: banknote transport means (FIG. 1) for sequentially transporting banknotes (1) through a reading station (4). 6 and 7), radiation beam generator means (5) for emitting a radiation beam on each banknote (1) as the banknote (1) passes through said reading station (4), and said radiation beam And an electronic reading means (6) for reading information encoded on the bill (1), which responds to the bill.