JPH10302111A - Device for authenticating paper sheet or the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To exclude the paper money, exchange ticket for money, etc., which are duplicated by a color copying machine, etc., by comparing the detection value information acquired from the output signal of of a light receiving part where the reflected light of the paper sheets, etc., are detected with the reference value information, thereby deciding the authenticy of the paper money, etc. SOLUTION: A light source 102 and a lens 103 are positioned so as to set a focal point at a position near the surface of a paper sheet 101. The sheet 101 is irradiated by light beams, that are narrowed less than the width of each print line or the between these lines of the sheet 101 in the form of a fine spot, and the printed ultra-fine lines can be analyzed. The sheet 101 is moved in the vertical or horizontal direction and the intensity of its reflected light varies according to the presence or absence of printed lines. The intensity variation of the reflected light undergoes the photoelectric conversion via a photodetector 104, and a signal (a) is outputted. The signal (a) undergoes the modulation of its intensity via the printed lines and accordingly the signal (a) that passed through a comparator 201 has a rectangular wave owing to the comparison performed with the reference value (b). The rectangular wave signal is turned into a voltage signal that is proportional to the frequency by an F/V converter 202, so that the pitch of the printed line is measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for judging the authenticity of paper sheets such as bills and notes.

[0002]

2. Description of the Related Art In recent years, with the increasing demand for automation and labor saving in vending machines, banks, etc., paper sheets represented by bills and bills (hereinafter, bills and bills are abbreviated as bills). In many cases, a transaction is processed by automatically determining whether the transaction is true or false. On the other hand, with the spread of color copiers, color printers, and the like, copying of such paper sheets has become easier. Various methods have been conventionally proposed for automatic discrimination of paper sheets, but each of them is composed of a detection unit 1, a processing unit 2, and a determination unit 3 shown in FIG. 1, and the functions of these units are described below. Of the techniques, the discriminating apparatus is often a combination of several methods.

1) A method for detecting the density distribution of magnetic ink printed on paper sheets: Japanese Patent Publication No. 61-13638, Japanese Patent Publication No.
No. 63785, Japanese Patent Publication No. 54-29396, Japanese Patent Publication No. 5
No. 8-43793, Japanese Patent Publication No. 55-21394, Japanese Patent Publication No. 3-19994, and the like. 2) A method of detecting the intensity distribution of light reflection and transmission of printing on paper sheets: Japanese Patent Publication No. 5-26385, JP-A-53-329.
5, No. 6-48511, etc. 3) Method for measuring the climax of intaglio printing on paper sheets:
JP-A-6-171071 and the like. 4) A method for detecting the length of paper sheets: Japanese Patent Publication No. 58-42
No. 913 and Japanese Patent Publication No. 58-9989. 5) Compound detection method: Japanese Patent Publication No. 22434
No., Japanese Patent Publication No. 4-313, Japanese Patent Publication No. 2-56713, etc. 6) Other methods: JP-A-6-215223, JP-B-3-15795, and the like.

[0004]

In the conventional method of discriminating false paper sheets by detecting the magnetic or optical distribution of the printing of the paper sheets, noise in the discrimination process and the process of distribution are considered. It is necessary to set the allowable value of the judgment to be considerably wide in consideration of the change of the paper sheet due to the above. On the other hand, as described above, the performance of devices such as a color copier, a color printer, a magnetic copier, and a magnetic pencil has been improved and the spread of paper sheets has become easier due to the widespread use. There was a risk that a counterfeit note would be accepted as a genuine note.

Further, in the judgment method based on the measurement of minute swelling in printing of paper sheets, the line width and line pitch of printing cannot be measured, and only means such as comparison of the number of positions within an allowable error at the minute bottom can be taken.

The present invention has been made under such a background, and it is possible to improve the reliability of an automatic paper sheet discriminating apparatus by eliminating bills and bills copied by a color copying machine or the like. An object of the present invention is to provide a device for determining the authenticity of paper sheets.

[0007]

According to a first aspect of the present invention, there is provided a light projecting unit which irradiates a print line printed on a paper sheet with a light beam narrower than the width of the print line or the interval between the print lines. And a light-receiving unit for detecting the reflected light from the paper sheet. Detected value information is obtained from a signal output from the light-receiving unit, and the detected value information is compared with the reference value information to determine the authenticity. The present invention provides a device for determining the authenticity of paper sheets.

According to a second aspect of the present invention, there is provided a light projecting section for irradiating a print line printed on a sheet with a light beam narrowed down to a width of the print line or an interval between the print lines; A light-receiving section for detecting transmitted light of the sheet, detecting value information from a signal output from the light-receiving section, and comparing the detected value information with reference value information to determine whether the sheet is authentic. A determination device is provided.

According to a third aspect of the present invention, in the paper sheet authenticity discriminating apparatus according to the first or second aspect, the detection value information is a line pitch of a printing line. .

According to a fourth aspect of the present invention, in the paper sheet authenticity discriminating apparatus according to any one of the first to third aspects, the detected value information is a ratio between a print portion and a non-print portion. It is characterized by being.

According to a fifth aspect of the present invention, in the paper sheet authenticity discriminating apparatus according to any one of the first to fourth aspects, the detected value information is an average width of a print line. Features.

According to a sixth aspect of the present invention, in the paper sheet authenticity discriminating apparatus according to any one of the first to fifth aspects, the detected value information includes a frequency distribution of a classified printing line width. It is characterized by being.

According to a seventh aspect of the present invention, in the paper sheet authenticity discriminating apparatus according to any one of the first to sixth aspects, the detected value information includes a frequency distribution of a printing line pitch classified into classes. It is characterized by being.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating a functional configuration of a paper sheet authenticity discriminating apparatus, and includes a detecting unit 1, a processing unit 2, and a determining unit 3. Here, two embodiments of the detection unit 1 of the present invention will be presented and described, and four embodiments of the processing unit 2 and the determination unit 3 will be described.

FIG. 2 is a diagram showing the configuration of a first embodiment of the detection unit 1 of the paper sheet authenticity discriminating apparatus according to the present invention.
In this figure, reference numeral 101 denotes paper sheets such as bills and notes, 102 denotes a light emitting element serving as a light source, and 103 denotes a light source 102
Reference numeral 104 denotes a light receiving element for detecting the intensity of light reflected on the surface of the paper sheet.

The light source 102 and the lens 103 are
1. The paper sheet 101 is arranged so as to be focused near the surface of the paper sheet 1, and irradiates the paper sheet 101 with a fine spot as a light beam narrower than the width of the print line of the paper sheet or the interval between the print lines. Be able to resolve fine lines. Paper sheets 101
Is moved in a vertical direction or a horizontal direction in FIG. 2 by a transport device (not shown), and the intensity of the reflected light changes depending on the presence or absence of a printing line. The intensity change of the reflected light is photoelectrically converted by the light receiving element 104, FIGS.
0, a signal a shown in FIG. 12 is output.

FIG. 3 is a diagram showing the configuration of a second embodiment of the detection unit 1 based on transmitted light of the paper sheet authenticity discriminating apparatus according to the present invention. 2 uses the reflected light of the paper sheet 101, but FIG. 3 differs from FIG. 2 in that the transmitted light of the paper sheet 101 is used. The arrangement is different between FIG. 2 and FIG. 3 due to the difference in reflection and transmission, but the operation is almost the same.

That is, light is applied to the paper sheet 101 from a light source 102 through a lens 103 so as to be focused on the surface of the paper sheet 101, and this light is transmitted through the paper sheet 101 and received by a light receiving element. The light reaches 104 and is received. Thus, the use of transmitted light complicates the signal obtained,
Since both front and back print information is included and detected,
If there is an inconsistency in the printing position on the back, the state of the signal a changes with respect to the normal one, and this is an effective means for authenticity determination.

FIG. 4 is a block diagram showing a circuit configuration of a first embodiment of a processing unit for obtaining a pitch of a print line from the output signal a of the detection unit 1 shown in FIG. 2 or FIG. In this figure, reference numeral 201 denotes a comparator that distinguishes whether an input signal a is a printed portion or a non-printed portion using a reference value b as a threshold value, and 202 denotes an F that converts the frequency of the signal into a voltage.
A / V converter 203 is an A / D converter for digitizing the analog output of the F / V converter 202.

First, since the signal a photoelectrically converted by the light receiving element 104 is subjected to intensity modulation by a printing line, the signal a passed through the comparator 201 becomes a rectangular wave by being compared with the reference value b. Next, the rectangular wave signal processed by the comparator 201 becomes a voltage signal proportional to the frequency by the F / V converter 202.

Therefore, the pitch of the print line can be measured by the processing unit. FIG. 5 shows the waveform of each part of the pitch measurement. In FIG. 5, the left end and the right end of the paper sheet 101 having a high density of the printing unit are the F / V converter 202.
Near the center where the output is high and the density of the printing section is low.
The output of the / V converter is low.

FIG. 6 shows a sheet 1 based on the output c of the processing unit.
13 is a flowchart for explaining the operation of a determination unit for determining whether the value is 01. In this determination unit, the type of the paper sheet 101,
Reference value d of the change in pitch of the print line corresponding to the insertion direction, etc.
Are stored including the allowable range.

The operation of the determination unit is as follows. First, the data c input in step s11 is compared with the first reference value d fetched in step s12 (s13), and if there is a match, it is determined to be true ( s14), the type is discriminated, and accompanying necessary processing is performed and output (s15), and the determination ends. If the data c does not match the captured reference value d, it is determined in step s16 whether or not this reference value d is the last reference value.
The next reference value d is fetched (s17) and compared with the measured value c (s13). If the reference value d does not match any of the stored reference values d, it is determined to be false (s18), and accompanying necessary processing is performed. Output (s19) and end the determination.

FIG. 7 is a block diagram showing a circuit configuration of a second embodiment of the processing unit 2 for obtaining a ratio of a print portion and a non-print portion from the output a of the detection unit 1 shown in FIG. 2 or FIG. Is performed. Reference value b, comparator 201
Is similar to FIG. 204 is an AND circuit, 205 is a counter circuit, 206 is a latch circuit, e is a clock signal,
f is a counter reset signal, g is a latch signal, and h is the output of this processing unit.

In this figure, a clock signal e is a square wave signal processed by a comparator 201 and an AND circuit 20.
The logical product is obtained by 4 and becomes effective in the print portion, and the number is counted by the counter circuit 205. Paper 10
The counter reset signal f and the latch signal g are generated at an appropriate timing by an encoder or the like mounted on one transport device, and the counter circuit 205 is appropriately cleared and repeated by the counter reset signal f. The count value is stored in the latch circuit 206 by the latch signal g and output. In this way, the processing unit in FIG. 7 can measure the length of the printed portion (the ratio between the printed portion and the non-printed portion) for each portion of the sheet 101.

FIG. 8 is a waveform diagram showing the relationship between the printing portion of the paper sheet 101, the comparator output, the clock signal e, and the AND circuit output.

FIG. 9 is a flowchart showing the operation of the determination unit for the output h of the processing unit in FIG. In this determination unit, a reference value i of a change in the ratio between the printed portion and the non-printed portion corresponding to the type of the sheet 101, the insertion direction, and the like is stored, including the allowable range. The operation of the determination unit is as follows. First, the data h input in step s21 is compared with the first reference value i captured in step s22 (s23), and if there is a match, it is determined to be true (s24). The type is discriminated and accompanying necessary processing is performed and output (s25), and the determination ends.

If the data h does not coincide with the reference value i, it is determined in step s26 whether or not this reference value i is the last reference value.
The next reference value i is sequentially taken in (s27) and compared with the measured value h (s23). If the reference value i does not match any of the stored reference values i, it is determined to be false (s28), and the accompanying necessary processing is performed. The output is performed (s29), and the determination ends.

FIG. 10 is a block diagram showing a circuit configuration of a processing unit for obtaining an average width of a print line from the output a of the detection unit 1 shown in FIG. 2 or 3 according to the third embodiment of the processing unit 2. is there. In this figure, a comparator 201, an AND circuit 204, a counter circuit 205, a latch circuit 20
6, threshold value b, clock signal e, counter reset signal f, and latch signal g are the same as those in FIG. Reference numeral 207 denotes a counter circuit that counts the number of print lines, 208 denotes a latch circuit that stores the number of print lines, and 209 denotes a division circuit that divides the length of the print lines by the number of print lines. This processing unit outputs the average width of the print line in a predetermined section as j.

FIG. 11 is a flowchart showing the operation of the determination unit for the output j of the processing unit in FIG. 10 according to the third embodiment of the processing unit 2. In this determination unit, the reference value k of the print line width change corresponding to the type, insertion direction, etc. of the paper sheet 101 is stored including its allowable range. The determination procedure is the same as that of FIGS. Is the same.

FIG. 12 shows a circuit configuration of a processing unit for obtaining a frequency distribution for each class of a printing line width from the output a of the detection unit 1 shown in FIG. 2 or 3 according to a fourth embodiment of the processing unit 2. FIG. 7, a comparator 201, an AND circuit 204, a counter circuit 205, a latch circuit 206, a threshold value b, a clock signal e, a counter reset signal f, and a latch signal g are shown in FIG.
Is the same as 210 is an inversion circuit, 211 is one line-
n-line demultiplexer, 212-1, 212-
2, 212-3... Are counter circuits, 213-1 and 22-1.
.. Represent latch circuits, l is a frequency count clock signal, and m-1, m-2, m-3.

In this processing section, the counter 205 is reset when the comparator 201 detects a print line,
The clock signal e is counted. At the end of the print line, the contents of the counter are stored in the latch circuit 206 as a latch signal through an inversion circuit 210 that inverts the output of the comparator 201. The 1-line / n-line demultiplexer 211 adds the frequency count clock l to the counters 212-1... According to the combination of the counted bits.

The counter reset signal f and the latch signal g are generated at an appropriate time by an encoder or the like installed in the conveying device of the paper sheet 101, and the counter circuits 212-1 are appropriately cleared by the counter reset signal f. , The count is repeated. Also, the count value is stored in the latch circuits 213-1.
.., M1, 3,... In this way, the frequency of each class of the print line width can be measured for each portion of the paper sheet 101 by the main processing unit.

FIG. 13 shows the reference value n-1 of the processing unit in FIG.
9 is a flowchart illustrating an operation of a determination unit that determines an output m−1 with respect to. In this determination unit, the type of the paper sheet 101,
The reference value n-1 of the change in the printing line width corresponding to the insertion direction and the like is stored including the allowable range, and the procedure of the determination is the same as that in FIGS. The same applies to the operation of the determination unit for the outputs m-2... With respect to the reference values n-2.

FIG. 14 is a circuit diagram of a processing unit for obtaining a frequency distribution for each class of a printing line pitch from the output a of the detection unit 1 shown in FIG. 2 or 3 according to a fifth embodiment of the processing unit 2. FIG. In this figure, a comparator 201, a counter circuit 205, a latch circuit 206, a 1-n line demultiplexer 21
1, counter 212-1 ..., latch 213-1 ...
The threshold value b, clock signal e, frequency count clock 1, counter reset signal f, and latch signal g are the same as those in FIG. 214 is a rising edge detection circuit;
Reference numeral 5 denotes a delay circuit, and p-1, p-2, p-3,...

In this processing section, the comparator 201
Detects a print line, uses this as a latch signal, and counts the count value of the clock signal e up to that time.
And the counter 205 is reset through the delay circuit 215 to start counting the clock signal e anew. In this way, the pitch of the print line is measured. The method of obtaining the frequency of each class from the measured print line pitch is the same as that in FIG.
2, p-3... Are output.

The operation of the basic embodiment of the present invention has been described above in detail with reference to the drawings. However, the present invention is not limited to this embodiment, and a design within a range not departing from the gist of the present invention. Modifications and the like are included in the present invention. For example,
By combining two or more different discrimination methods described above, it is possible to improve the reliability of paper sheet authenticity discrimination. Although the above embodiment has been described with reference to an example in which the circuit is constituted by a discrete circuit, the embodiment may be constituted by using a CPU.

[0038]

As described above, according to the present invention, a light beam narrower than the width of the print line printed on the paper sheet or the interval between the print lines is irradiated, and the reflected light or transmitted light is transmitted. Detecting ultra-fine lines with light, detecting one or more of the printing line pitch, the average width of the printing line, the ratio of the printing part or the non-printing part, or the frequency distribution of the printing line width classified, Authenticity determination is performed without being affected by changes in printing conditions during the distribution of paper sheets, so the effect that color copiers and photoengraving objects can be discriminated can be determined. Is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a functional configuration of a paper sheet authenticity discriminating apparatus.

FIG. 2 is a diagram illustrating a configuration of a detection unit that detects reflected light according to the first embodiment of the detection unit according to the present invention.

FIG. 3 is a diagram illustrating a configuration of a detection unit that detects transmitted light according to a second embodiment of the detection unit according to the present invention.

FIG. 4 is a block diagram showing a circuit configuration of a processing unit for obtaining a pitch of a print line from a signal of a detection unit in the first embodiment of the processing unit according to the present invention.

FIG. 5 is a waveform diagram of each part of the measurement of the pitch of a print line according to the first embodiment of the processing unit.

FIG. 6 is a flowchart illustrating an operation of a determination unit that determines the authenticity of a sheet according to the first embodiment of the processing unit.

FIG. 7 is a block diagram showing a circuit configuration of a processing unit for obtaining a ratio of a printed portion and a non-printed portion according to a second embodiment of the processing unit according to the present invention.

FIG. 8 is a waveform diagram of each part of a processing unit for obtaining a ratio between a printed portion and a non-printed portion according to the second embodiment of the processing unit.

FIG. 9 is a flowchart illustrating the operation of a determination unit that determines the authenticity of a sheet according to a second embodiment of the processing unit.

FIG. 10 is a block diagram showing a circuit configuration of a processing unit for obtaining an average width of a print line from a detection unit output according to a third embodiment of the processing unit according to the present invention.

FIG. 11 is a flowchart illustrating an operation of a determining unit that determines whether the usage is authentic according to the third embodiment of the processing unit.

FIG. 12 is a block diagram showing a circuit configuration of a processing unit for obtaining a frequency distribution for each class of a printing line width from a detection unit output according to a fourth embodiment of the processing unit according to the present invention.

FIG. 13 is a flowchart illustrating an operation of a determination unit that determines whether the usage is authentic according to the fourth embodiment of the processing unit.

FIG. 14 is a block diagram showing a circuit configuration of a processing unit for obtaining a frequency distribution for each class of a printing line pitch from a detection unit output according to a fifth embodiment of the processing unit according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Detection part 2 Processing part 3 Judgment part 101 Sheet 102 Light source 103 Lens 104 Light receiving element

Claims (7)

[Claims] 1. A light projecting unit which irradiates a print line printed on a sheet with a light beam narrowed down to a width of the print line or an interval between the print lines, and detects reflected light from the sheet. A detection unit for detecting detection value information from a signal output from the reception unit;
A paper sheet authenticity discriminating apparatus that judges the authenticity by comparing the detected value information with the reference value information. 2. A light projecting unit for applying a light beam narrowed to a width of a printing line or an interval between the printing lines to a printing line printed on a sheet, and a light receiving unit for detecting transmitted light of the sheet. The detection value information is obtained from the signal output from the light receiving section,
A paper sheet authenticity discriminating apparatus that judges the authenticity by comparing the detected value information with the reference value information. 3. The apparatus according to claim 1, wherein the detection value information is a line pitch of a print line. 4. The apparatus according to claim 1, wherein the detection value information is a ratio between a printed portion and a non-printed portion. 5. The apparatus according to claim 1, wherein the detection value information is an average width of a print line. 6. The apparatus according to claim 1, wherein the detection value information is a frequency distribution of print line widths classified into different classes. 7. The paper sheet authenticity discriminating apparatus according to claim 1, wherein the detected value information is a frequency distribution of print line pitches classified.