JPS59231691A - Discrimination system for sheet papers - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a paper sheet discrimination method that uses, for example, the color of a banknote to determine its type and authenticity.

[Technical background of the invention and its problems]

Various types of discrimination methods have been proposed in the past, but
A typical example is one that detects the color or turn of a banknote and calculates the degree of similarity between it and a standard pattern to determine the type and authenticity of the banknote. However, with such conventional discrimination methods, it is extremely difficult to obtain sufficient discrimination performance when distinguishing banknotes from other countries using only four turns of a single color.

[Purpose of the invention]

The present invention has been developed in view of the above circumstances, and its purpose is to be effective even when there are many types of paper sheets to be discriminated, or when paper sheets to be discriminated have similar printing colors. It is an object of the present invention to provide a method for discriminating paper sheets that is sufficiently compatible with the present invention and that also provides a high discriminating performance.

[Summary of the invention]

The present invention separates the reflected light from the front or back side of the paper sheet to be classified into a plurality of color regions, photoelectrically converts each color region, and calculates the color components using each photoelectric conversion signal. The type of paper sheet to be discriminated is determined by extracting pattern signals of 4 and performing calculations between each extracted 4-turn signal and a standard A' turn signal set in advance.

In addition, the present invention further integrates each of the above photoelectric conversion signals, calculates a color component using each integrated signal to obtain a calculated value, and the calculated value corresponds to the determined type. The authenticity of the paper sheet to be determined is determined based on whether or not it satisfies a standard value.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

In the figure, P denotes a banknote that is conveyed in the direction of the arrow in the figure, 1 a light source that illuminates the surface of the banknote P, and 2 a detector that separates the reflected light from the surface of the banknote P into colors and converts it into electricity. The detector 2 separates the reflected light from the surface of the banknote P into infrared (IR), red (R), blue (B), and blue (B) using a microchroic mirror or a glass filter, for example. Each of them is photoelectrically converted by a photoelectric conversion element, and as a result, four types of pattern signals IR and R are generated.
, G, and B are obtained. Each pattern signal IR, R, G, B thus obtained from the detector 2 is sent to the computing unit 3, respectively. The arithmetic unit 3 receives each input pattern signal IR,
By performing color calculations using R, G, and B, a plurality of nos and turns are extracted. That is, each calculation is performed using a plurality of calculation formulas that remove the influence of dirt on banknotes, for example, the two calculation formulas shown below, and each calculation result (pattern) IP, IP, is output. .

=IP.

R+G Therefore, each calculation result IP, , IP of the calculation unit 3.

are respectively sent to the similarity calculator 4. Similarity calculator 4
is the input turn IP, , IP, and the standard turn R stored in the standard turn memory 5.
P1. By performing similarity calculations between RP and RP, the type of banknote P is determined, and the determination result is output. The above similarity calculation is performed, for example, using the calculation formula shown below.

That is, the degree of similarity with all standard Noreens is calculated, and the standard pattern having a large degree of similarity is determined to be the type of banknote. In this case, input/4 turner IPI
, IF5, so add their similarities (
s, + St) L,, the standard pattern showing the greatest degree of similarity is the result of that person's Kanoktan.

In addition, each turn signal IR obtained from the detector 2
, R, G, and B are sent to an integrator 6, respectively. The integrator 6 receives each input gloss turn signal IR, R, G, B.
f is integrated, and each integrated signal flR, fR, , f
Output G and fB, respectively.

These output integral signals, fl R, JR, , fG
, fB are each sent to the arithmetic unit 7. The arithmetic unit 7 receives each input integral signal, fIR, fR, fG, f
By performing color calculation using B, a plurality of calculated values are output. That is, for example, calculations are performed using multiple calculation formulas that can remove the influence of dirt on banknotes and obtain a stable amount of a special color, for example, the four calculation formulas shown below, and the results of each calculation are calculated. CI+”t
Output r ”11 v C4.

Therefore, each calculation result of the calculation unit 7 CIr"t+C3
, C4 are sent to the comparator 8, respectively. The comparator 8 also includes the similarity factor 4. The type discrimination result output from the device 4 is also supplied. Thereby, the comparator 8 reads out the corresponding reference value from the reference value memory 9 according to the above-mentioned type discrimination result, and each input calculation result CI! C2+
c, l c.

By comparing the calculation results with the standard values, the banknote is determined to be a genuine banknote, and otherwise, the banknote is determined to be a counterfeit banknote, and the determination results are output.

According to the discrimination method explained above, the properties of the input/base turn are extremely stable, and high discrimination performance can be obtained.8 Furthermore, since multiple inputs/base turns are used, the fffl type of the banknotes handled is It has sufficient discrimination performance when there are many banknotes, when the printing colors are similar, and when distinguishing between banknotes from other countries. This enables accurate discrimination. Furthermore, it is possible to extract a stable amount of colors that can be used for authenticity determination from among the printed colors of banknotes, thus making it possible to perform more stable and accurate authenticity determination.

In the above embodiments, the case where the discrimination is performed using the light reflected from the surface of the banknote has been described, but it can also be applied to the case where the discrimination is performed using the light reflected from the IS surface or the light emitted from both layers. Also, the f of banknotes! Class Ii has been described for the case of determining authenticity, but the invention is not limited to this, and for example, types of paper sheets other than banknotes, such as checks or other securities.

It can also be applied to determining authenticity.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to sufficiently deal with cases where there are many types of paper sheets to be discriminated, or paper sheets to be discriminated with similar printing colors, and moreover, high discrimination performance can be obtained. It is possible to provide a method for identifying paper sheets that can be used.

[Brief explanation of the drawing]

The figure is a block diagram for explaining one embodiment of the present invention. P... Banknote (paper sheet), 1... Light source, 2... Detector, 3... Arithmetic unit, 4... Similarity computing unit, 5...
Standard / turn memory, 6... Integrator, 7... Arithmetic unit, 8... Comparator, 9... Reference value memory.

Claims (2)

[Claims] (1) Using a photoelectric conversion means that separates the reflected light from the front or back side of the paper sheet to be classified into multiple color regions and photoelectrically converts each color region, and an output signal for each color region obtained from the photoelectric conversion means. A calculation means extracts a plurality of pattern signals by calculating color components, and calculations are performed between each pattern signal obtained from this calculation means and a standard/main turn signal set in advance. 1. A method for discriminating paper sheets, comprising: discriminating means for discriminating the type of paper sheets to be discriminated by performing the method. (2) Using a photoelectric conversion means that separates the reflected light from the front or back side of the paper sheet to be classified into multiple color regions and photoelectrically converts each color region, and an output signal for each color region obtained from this photoelectric conversion means. A first calculation means for extracting a plurality of pattern signals by calculating color components, and a calculation is performed between each of the 74-tone signals obtained from the first calculation means and a standard pattern signal set in advance. a first discriminating means for discriminating the type of paper sheet to be discriminated by
an integrating means for respectively integrating the output signal for each color region obtained from the photoelectric conversion means; and a second integrating means for calculating a color component using each integral signal obtained from the integrating means and outputting a calculated value. a calculating means; and a second calculating means for determining the authenticity of the paper sheet to be determined based on whether the calculated value outputted from the second calculating means satisfies a reference value corresponding to the type determined by the first determining means. 2. A method for discriminating paper sheets, characterized by comprising: two discriminating means.