JPH06195541A - Paper money discriminating method for paper money discriminating device - Google Patents

Abstract

PURPOSE:To improve the probability of discrimination of paper money by detecting visible rays by a photodetecting element and comparing constant data in the time-series data of the obtained transmitted visible rays with corresponding position data in time-series data in the same detection zone of genuine paper money. CONSTITUTION:When a sensor 3 detects the paper money 1 reaching a specific position, an A/D converter 4 begins to operate. The detection signal of the visible rays which are emitted by the light emitting diode 2a of a sensor unit 2, transmitted through the detection zone of the paper money 1, and detected by a phototransistor 2b is sampled in synchronism with the moving speed of the paper money 1 by a roller group, and then quantized and encoded. Then each time the output of a counter 5 reaches a corresponding numeral, reference data in a ROM 6 are read in a decision means 7 and compared with the output of the A/D converter 4. It is judged whether or not the difference is within a permissible range and when the difference is within the permissible range, a signal showing that the paper money is genuine is outputted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bill identifying method for identifying the authenticity of bills.

[0002]

2. Description of the Related Art Techniques such as pattern recognition have been adopted for discriminating bills, but recently, excellent copying apparatuses have become widespread, and it is difficult to discriminate copy bills from genuine bills by these techniques. Has become. There is also a technique in which the magnetic pattern due to the magnetic substance contained in the ink of the banknote is detected by a magnetic sensor and at the same time the size and the like of the banknote are detected and compared with reference data to identify the authenticity.

However, the time-series detection data of a certain detection zone by the above magnetic sensor is unstable because it becomes different data for each inspection even for the same bill. There is also a method of using near-infrared rays and seeing the pattern of differences depending on the content of near-infrared ray absorption contained in the ink, but there are some foreign currency bills that do not use ink that absorbs near-infrared rays. Some are difficult.

[0004]

Banknotes range from genuine notes that have just been issued to used notes that are circulated and dirty, and even the same banknote becomes a factor for banknote identification depending on the degree of circulation. Optical characteristics, magnetic characteristics,
There are large variations in dimensional characteristics, color characteristics, and so on.

Therefore, it is in a state in which it cannot be easily identified by the above-mentioned technique or the like. Therefore, an object of the present invention is to provide an identification method that is not affected by variations in the identification factors as described above, and to increase the probability of identifying banknotes.

[0006]

The gist of the constitution of the present invention is that a sensor unit consisting of a light-emitting element for emitting red and green visible light rays and a light-receiving element for receiving the transmitted light is provided for a banknote to be inspected. Travel along the detection zone, the visible light emitted from the light emitting element, transmitted through the detection zone of the banknote is detected by the light receiving element, the constant data in the time-series data of the transmitted visible light obtained. Is a discrimination method for comparing bills with data of corresponding positions in time series data in the same detection zone of genuine bills, and discriminating bills based on the difference.

In this specification, "printing" includes various copying techniques. In addition, "visible light" means that in the wavelength range of 450 nm to 700 nm in visible light.

The light emitting element and the light receiving element are preferably of quantum type suitable for use in the above visible light range.
Further, the reference data is a bill-like product preliminarily printed on a genuine bill and a magnetic copy product of a genuine bill, each of which is a sensor unit composed of a light-emitting element and a light-receiving element of the visible light, along a predetermined detection zone. Scanning to obtain each time series data, there is no difference between new and old notes in the time series data of genuine bills, and there are multiple positions where stable data can be obtained by repeated inspection. The data at a plurality of positions where there is a significant difference between the data of the banknote similar product and the data of the magnetic copy product are adopted. Naturally, each of the above-mentioned reference data is held together with the information on the detection position.

By the way, the output of the sensor unit can be processed by a general digital technique.

For example, the output of the light receiving element of the sensor unit is sampled at an appropriate sampling frequency, and the obtained samples are sequentially converted into digital data by an A / D converter. On the other hand, the number of samples is counted from the starting point of the sample, and the digital data corresponding to a predetermined count value sample is input to the determination means and compared with the corresponding reference data held in the storage means such as the ROM.

The correspondence between the digital data of the sample and the reference data is determined by the correspondence between the count value of the sample and the information on the detection position of the reference data. The count value indicates the detection position of the corresponding sample by the sensor unit. Therefore, the information on the detection position of the reference data is a numerical value corresponding to the count value of the sample,
Alternatively, it is preferable to use the address of the storage means expressed by a numerical value obtained by performing a process such as multiplying this by an appropriate count. Naturally, the corresponding reference data is held at the corresponding address of the storage means.

Then, as described above, the determination means compares the digital data at the predetermined detection position of the bill to be inspected with the corresponding reference data, and determines whether the difference is within the allowable dimension.

Based on the comparison result, the judging means judges whether the bill to be inspected is a genuine bill, outputs a corresponding signal, and the bill is accepted or returned based on the signal.

[0014]

The present invention, having the above-mentioned structure, operates as follows.

With respect to the bill to be inspected, the sensor unit including the light emitting element and the light receiving element of the visible light is scanned along the detection zone to obtain time series data. In this case, it is the same whether the sensor unit is moved or the bill is moved.

In the time-series data, the data at the selected plurality of positions are compared with the corresponding reference data, and it is determined whether or not the difference between them exceeds the allowable range. As a result, if the difference is within the allowable range, it is determined that it is a genuine bill, and if it exceeds this, it is determined that it is not a genuine bill.

This determination is carried out by lithographic printing, magnetic copying,
Since there is a significant difference in the absorption rate of visible light at the corresponding position from intaglio printing (genuine bill), it can be easily performed.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

This embodiment is applied to a vending machine. The vending machine mechanism is omitted.

As shown in FIG. 1, the inserted banknote 1 is drawn into the banknote insertion slot by a commonly used roller group (not shown) and passes immediately below the phototransistor 2b at a constant speed. It is configured as follows. Immediately before the phototransistor 2b, a sensor 3 for detecting the position of the banknote 1 is arranged to detect when the inserted banknote 1 reaches a predetermined position, and the detection signal is detected by an A / D converter. Input to 4 and A / D at that timing
It is configured to initiate the conversion.

The sensor unit 2 is a photo sensor, which is composed of a light emitting diode 2a which emits red light having a peak emission wavelength of 650 nm and green light having a wavelength of 560 nm and a phototransistor 2b which detects a transmitted light ray. As described above, visible light is emitted from the light emitting diode 2a to the detection zone of the banknote 1 passing directly under it, and the transmitted light is detected by the phototransistor 2b.
The detection signal of the phototransistor 2b is input to the A / D converter 4, and is sampled at a predetermined sampling frequency that is synchronized with the bill 1 withdrawal speed of the roller group, and subsequently, quantization and encoding are sequentially performed. The sampling number of the A / D converter 4 is counted by the counter 5 connected to it, and its output is stored in the ROM 6
And to input to the determination means 7. When the output is input, the counting of the sampling number is started at the same time.

The ROM 6 stores the transmitted light beam data at a plurality of predetermined detection positions of the genuine bill 1 as reference data. The address of the ROM 6 storing the reference data corresponds to the sampling number corresponding to each detection position. That is, when the detected position of the fifth sampled data matches the detected position of the reference data, the reference data is stored in the address (5) of the ROM 6.

As the reference data, the genuine banknote 1 and a banknote-like product printed by lithographic printing and a magnetic copy product of a genuine banknote are scanned by the sensor unit 2 along the same detection zone in advance. , The time series data of the authentic banknote 1 is a plurality of positions in the time series data of the authentic banknote 1 where there is no difference between genuine banknotes and old banknotes and stable data can be obtained by repeated scanning. The respective data of the product and the magnetically copied product and the data of the remarkable authentic bill 1 are stored in the corresponding addresses of the ROM 6 as described above.

The output of the counter 5 is the bill 1 under inspection.
The detection data of the corresponding sample, that is, the output of the A / D converter 4 and the reference data, that is, the data of the corresponding address of the ROM 6 are compared and examined by the determination means 7. The judging means 7 is constructed so that when a numerical value corresponding to the address where the reference data is stored in the ROM 6 is input from the counter 5, the same numerical value of the counter 5 is simultaneously input to this and the operation is started. There is.

The judging means 7 compares the reference data with the output of the A / D converter 4 and judges whether the difference is within the allowable range. The allowable range is determined in consideration of the difference between the printing techniques obtained when the above-mentioned standard data is determined.
In any case, since there is a remarkable difference as described above, the allowable range can be set with a margin.

The inspection target bill 1 is accepted by the determination output of the determination means 7 indicating that it is an authentic bill, and is returned by the output indicating that it is not.

When the bill 1 is inserted into the bill insertion slot, the bill 1 is pulled by the roller group. Subsequently, when the sensor 3 detects that the bill 1 has reached a predetermined position, the detection signal causes the A / D converter 4 to start operating, and the light emitting diode 2a of the sensor unit 2 irradiates the bill 1 to the bill. A detection signal of visible light which is transmitted from the detection zone and detected by the phototransistor 2b is sampled in synchronization with the moving speed of the banknote 1 by the roller group, and then is quantized and encoded. The output of the sensor 3 is also input to the counter 5 at the same time, and the number of samplings of the A / D converter 4 is simultaneously counted.

Each time the output (sampling number) of the counter 5 reaches a corresponding numerical value, the reference data of the ROM 6 is read by the judging means 7, and the output of the A / D converter 4 (detection of the bill 1 at the corresponding position). Data). Then, it is determined whether or not the difference belongs to the allowable range. If the difference falls within the allowable range, a signal indicating that the bill is an authentic bill is output, and the inserted bill 1 is accepted. Is not output and the bill 1 is returned.

[0029]

According to the present invention, the difference in the printing technique can be identified by using the difference in the absorptance of visible light as an index for the determination, and as a result, the authenticity can be easily and accurately determined.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of an example of the present invention.

[Explanation of symbols]

 1. Banknote 2. Sensor unit 2a. Light emitting diode 2b. Phototransistor 3. Sensor 4. A / D converter 5. Counter 6. ROM 7. Judgment means

Claims (1)

[Claims] 1. A visible light transmitted through a detection zone of a bill to be inspected by scanning a sensor unit including red and green emitting elements and a light receiving element for receiving the transmitted light, along a detection zone of the bill to be inspected. Is detected by the above light receiving element,
This is an identification method in which banknotes are identified by comparison with certain data in the obtained time-series data of visible light and the difference.