WO2016093439A1

WO2016093439A1 - Bill processing apparatus and method for detecting counterfeit bills by means of same

Info

Publication number: WO2016093439A1
Application number: PCT/KR2015/004150
Authority: WO
Inventors: 박성수; 김학수
Original assignee: (주)비티비코리아
Priority date: 2014-12-10
Filing date: 2015-04-27
Publication date: 2016-06-16
Also published as: KR101573656B1; KR20160070663A

Abstract

The present invention relates to a bill processing apparatus capable of detecting counterfeit bills, and a method for detecting counterfeit bills by means of the bill processing apparatus, the bill processing apparatus comprising: a bill input unit for receiving one or more bills; a transport unit for transporting the inputted bills; a light-emitting unit for irradiating the bills transported by the transport unit with infra-red light by means of an LED emitting infra-red light; a light-receiving unit for detecting the light discharged from an anti-Stokes substance on the bill due to the infra-red light irradiated thereon; and a counterfeit bill determination unit for determining whether a bill is a counterfeit by means of the light detected by the light-receiving unit.

Description

Banknote processing apparatus and counterfeit detection method using the same

The present invention relates to a bill processing apparatus capable of detecting a counterfeit bill.

As a method of detecting counterfeit of a banknote currently generally used, a method of measuring the form or position of a reaction position of ink for detecting a counterfeit bill is mainly used.

In addition, the method of measuring the transmission absorbance or reflectance of the ultraviolet light has a specific form, and has a method of measuring the lipid of the banknote or by using the transmission or reflectance of the ultraviolet reaction ink.

However, in recent years, the elaboration of counterfeit banknotes has become more sophisticated, and forgery of location information on geology, ultraviolet rays, or ink reaction regions of banknotes has caused problems in reliability.

Recognition of the problems and problems of the prior art described above is not obvious to those of ordinary skill in the art of the present invention and should not judge the progress of the present invention compared to the prior art based on such recognition. Reveal.

An object of the present invention for solving the above problems is to provide an apparatus and method that can detect counterfeit bills more accurately and easily.

Technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned above may be clearly understood by those skilled in the art from the following description. There will be.

Banknote processing apparatus according to an embodiment of the present invention, the banknote input unit for receiving one or more banknotes; A transfer unit for transferring the inserted banknotes; A light emitting unit for irradiating infrared light onto the banknote conveyed by the conveying unit by using a light emitting diode (LED) emitting infrared light; A light receiving unit for detecting light emitted from the anti-Stokes material formed on the banknote by the irradiated infrared light; And a counterfeit determination unit that determines whether the banknote is forged using the light detected through the light receiving unit.

Counterfeit detection method according to an embodiment of the present invention, the step of receiving one or more bills; Sequentially transferring the inserted bills; Irradiating infrared light onto at least one surface of the bill to be transferred using an LED emitting infrared light; Detecting light emitted from the anti-stoke material formed on the banknote by the irradiated infrared light; And determining whether the banknote is forged by using the detected size of light, wherein the anti-stokes material formed on the banknote absorbs the irradiated infrared light and then displays visible light having a lower wavelength than the infrared light. Release.

At least some steps of the forgery detection method may be implemented as a computer-readable recording medium having recorded thereon a program for execution in a computer.

According to one embodiment of the present invention, by irradiating the infrared rays to the bill using the infrared LED and thereby detects the light emitted from the anti-Stokes material formed on the bill to determine whether the counterfeit, it may be possible to more easily and accurately detect the counterfeit have.

The following drawings, which are attached to this specification, illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention serve to further understand the technical spirit of the present invention. It should not be construed as limited to.

1 is a view showing an embodiment of the configuration of a bill processing apparatus according to the present invention.

Figure 2 is a block diagram showing a simplified configuration of a bill processing apparatus according to an embodiment of the present invention.

3 is a flowchart illustrating a forgery detection method according to an embodiment of the present invention.

4 to 6 are views for explaining embodiments of the configuration of the infrared LED light emitting unit and the light receiving unit provided in the banknote processing apparatus.

7 to 9 are diagrams for explaining an embodiment of a method for detecting forgery using an anti-Stokes material formed on the bill.

10 is a block diagram showing an embodiment of the configuration of the counterfeit determination unit.

FIG. 11 is a graph for explaining an embodiment of a method of detecting the presence or absence of an anti-stock material by using an output signal of the light receiver.

12 is a circuit diagram illustrating an embodiment of a configuration of a light emitting unit.

13 is a circuit diagram illustrating an embodiment of a configuration of a light receiving unit.

FIG. 14 is a circuit diagram illustrating an embodiment of the configuration of the first amplifier illustrated in FIG. 10.

FIG. 15 is a circuit diagram illustrating an embodiment of the configuration of the integrator shown in FIG. 10.

16 is a circuit diagram showing an embodiment of the configuration of a circuit for controlling the operation of the integrator.

FIG. 17 is a circuit diagram illustrating an embodiment of a configuration of a second amplifier illustrated in FIG. 10.

The following merely illustrates the principles of the invention. Therefore, those skilled in the art, although not explicitly described or illustrated herein, can embody the principles of the present invention and invent various devices that fall within the spirit and scope of the present invention. Furthermore, all conditional terms and embodiments listed herein are in principle clearly intended for the purpose of understanding the concept of the invention and are not to be limited to the specifically listed embodiments and states. Should be.

In addition, it is to be understood that all detailed descriptions, including the principles, aspects, and embodiments of the present invention, as well as listing specific embodiments, are intended to include structural and functional equivalents of these matters. In addition, these equivalents should be understood to include not only equivalents now known, but also equivalents to be developed in the future, that is, all devices invented to perform the same function regardless of structure.

Accordingly, all flowcharts, state diagrams, pseudocodes, etc., should be understood to represent various processes performed by the computer or processor, whether the computer may be substantially represented on a readable medium and whether the computer or processor is clearly shown. .

The functionality of the various elements shown in the figures, including functional blocks represented by a processor or similar concept, can be provided by the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functionality may be provided by a single dedicated processor, by a single shared processor or by a plurality of individual processors, some of which may be shared.

The above objects, features, and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, whereby those skilled in the art may easily implement the technical idea of the present invention. There will be. In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows an embodiment of the configuration of the banknote processing apparatus according to the present invention, showing the inside of the device that can perform counting and counterfeit detection for one or more banknotes to be inserted.

Referring to FIG. 1, the banknote processing apparatus 10 may include rollers 110 which allow a plurality of banknotes loaded in an insert part 140 to be sequentially fed one by one, and a transfer state of the banknotes. It may be configured to include transfer sensors 120 for detecting and counterfeit detection sensors 130 for detecting whether the banknote is forged by being located adjacent to the transfer path T of the transferred banknote.

For example, the rollers 110 are main-feed rollers for conveying bills, pick-up rollers and separation rollers for separating the stacked bills into sheets and transferring them to the main-feed rollers. When the above bills are conveyed together, it may include a reverse roller for pushing the upper sheet in the opposite direction to separate the sheets.

Meanwhile, the transfer sensors 120 may include an input sensor for detecting whether a banknote is separated into sheets and a jam sensor for detecting a jam of banknotes in the middle of the transfer path T. Can be.

In addition, the counterfeit detection sensors 130 may include an infrared (IR) sensor, an ultraviolet (UV) sensor, a magnetic (MG) sensor, an ultrasonic (US) sensor, a CIS sensor, or the like, for detecting various counterfeit elements formed in a banknote. Can be.

The banknote processing apparatus 10 according to the embodiment of the present invention includes an anti-stoke sensor for detecting an anti-Stokes material formed in a specific region of the banknote to detect counterfeit.

First, Stokes' shift refers to a phenomenon in which a special material absorbs a photon and emits a photon having a wavelength spectrum different from that. Specifically, when a material composed of molecules or atoms absorbs a photon, energy is obtained. When the energy saturation state is released to have the original energy to emit again, when the energy of the emitted photons is less than the energy of the absorbed photons is called the Stokes shift phenomenon.

Anti-Stokes' shift, on the other hand, is a case where the energy of photons emitted is greater than the energy of photons absorbed, as opposed to the Stokes shift phenomenon, for example, infrared light having a wavelength of about 900 nm or more. If this is absorbed it may mean a phenomenon that is emitted by the visible light having a smaller wavelength and transition.

In other words, the anti-stork material is a material capable of emitting light in the visible range when excited by infrared (IR), and the rotation line of the Raman spectrum is called a Raman line, and the line appearing at a wavelength longer than the incident light is called a stokes line, a short wavelength. The line that appears on the side is called the anti-stokes line.

The Raman spectrum is a spectrum of scattered light due to the Raman effect. The Raman spectrum is referred to as a vibration Raman spectrum when an energy difference between the incident photons and a molecule is exchanged between the vibrational levels of molecules in a ground state.

In this case, since the transition between the rotational levels is also related, it is also called a Raman rotational vibration band, and the vibration quantum number is strongly changed by one. On the other hand, the spectrum in the case where the transmission and reception of energy differences between rotation levels within the lowest vibration level in the ground state occurs is called the rotational Raman spectrum.

On the other hand, the normal banknotes determined as not counterfeit by the configuration as described above is stacked in the stacker (stacker, 150), abnormal bills, such as judged as counterfeit or unable to confirm the denomination, such as a reject pocket (reject pocket, 160).

Figure 2 is a block diagram showing a simplified configuration of a bill processing apparatus according to an embodiment of the present invention, the bill processing apparatus 10 shown is a bill input unit 210, transfer unit 220, bill discharge unit 230 ), The controller 240, the light emitter 250, the light receiver 260, and the counterfeit determiner 270. A description of the same elements as those described with reference to FIG. 1 among the components of the bill processing apparatus shown in FIG. 2 will be omitted below.

Referring to FIG. 2, the banknote input unit 210 receives one or more banknotes, and the transfer unit 220 transfers the inserted banknotes.

On the other hand, the light emitting unit 250 may be irradiated with infrared light to the banknotes transferred by the transfer unit 220 using a light emitting diode (LED) that emits infrared light.

For example, the light emitter 250 may irradiate infrared light having a wavelength of about 930 nm to 1040 nm to a region where an anti-stoke material is formed on one surface of the transferred banknote.

The light receiver 260 may detect light emitted from the anti-stokes material formed on the banknote by the infrared light emitted by the light emitter 250, and output a light detection signal corresponding to the detected light size.

In addition, the counterfeit judging unit 270 determines whether the paper money is forged by using visible light detected by the light receiving unit 260, and after determining whether the paper money is forged, the paper money outward through the paper money discharge unit 230. May be discharged.

For example, the counterfeit judging unit 270 may determine whether the banknote is forged based on a voltage or a current corresponding to the size of visible light detected through the light receiving unit 260.

On the other hand, the control unit 240 serves to control the overall operation and functions of each component of the bill detection apparatus as described above.

3 is a flowchart illustrating a counterfeit detection method according to an embodiment of the present invention, and the block diagram showing the configuration of the banknote detecting device according to an embodiment of the present invention shown in FIG. Let's explain.

Referring to FIG. 3, first, the banknote inserting unit 210 receives one or more banknotes (step S300), and the transfer unit 220 sequentially transfers the inserted banknotes (step S310).

For example, as illustrated in FIG. 4, the banknote input unit 210 includes a pickup roller 410 and a separation roller 415 to separate the stacked banknotes into sheets and transmit them to the input sensor 420. Can play a role.

In addition, the input sensor 420 serves to detect whether the banknote is moved into a single sheet, and if the banknote is detected, the input sensor 420 is transferred to the controller 240 to emit the light 250 from the controller 240. It serves to control the operation of the.

On the other hand, the input sensor 420 may be made of two or more.

The light emitting unit 250 irradiates infrared light to at least one surface of the bill to be transferred using an LED emitting infrared light (S320).

For example, as shown in FIG. 5, the light emitting module 430 emits infrared light having a wavelength of 930 nm to 1040 nm using the infrared LED 431, and uses the convex lens 432 to emit light. Diffuse to increase the width of the light emitted so that the infrared light is irradiated on one surface of the bill (401).

The light receiving unit 260 detects visible light generated from the banknote by the infrared light emitted by the light emitting unit 250 (S330).

As described above, the visible light detected through the light receiving unit 260 may be emitted after the infrared light irradiated onto the banknote 401 by the anti-Stokes material formed on the banknote 401 is absorbed, 380nm to It may have a wavelength of 800 nm.

For that purpose, the light receiving module 440 includes a visible light filter 441 for filtering light having a wavelength of 380 nm to 800 nm and a light receiving sensor 443 for receiving light filtered through the visible light filter 441. can do.

Thereafter, the counterfeit judging unit 270 determines whether the banknote is forged using the visible light detected by the light receiving unit 260 (step S340).

For example, when the banknote 401 passes between the light emitting module 430 and the light receiving module 440 structure, the material or the general ink of the banknote 401 does not react and generates only infrared light, and the anti-stokes among the banknotes are generated. In the region where the anti-counterfeiting ink including the material is formed, visible light is emitted to transmit an optical signal or light to the light receiving module 440, and the amount of light is expressed as a current or voltage, and the measured voltage or current is measured. It is possible to determine the presence or absence of the anti-stoke substance and use the value to determine whether the bill is counterfeit.

When the combination of the light emitting unit 250 and the light receiving unit 260 that operates as described above is two or more, the bill processing apparatus 10 may be prevented from infrared light emitted from the light emitting unit 250 through the light receiving unit 260. After filtering the visible light emitted from the region in which the stokes material is formed through the visible light filter, current or voltage data corresponding to the optical signal or light received through the light receiving sensor may be sequentially stored.

Thereafter, the banknote processing apparatus 10 adds up the data reaching the specific level through the counterfeit determination unit 270 and counts the accumulated number of times, so that the number of times of reaching the specific level is set in advance (for example, three times). ) Or more, it can be determined as a normal bill, and if less than a predetermined number of times (for example, three times), it can be determined as a counterfeit bill.

As shown in FIG. 5, the light emitting module 430 and the light receiving module 440 are provided in a transmissive structure, so that the light receiving module 440 may detect the light passing through the banknote 401. The light emitting module 430 may be positioned at an opposite side of the light emitting module 430.

On the other hand, as shown in Figure 6, the light emitting module 430 and the light receiving module 440 is provided with a reflective structure, so that the light receiving module 440 can detect the light reflected from the banknote 401 ( The light emitting module 430 may be positioned on the same side with respect to the 401.

Hereinafter, with reference to FIGS. 7 to 9 will be described an embodiment of a method for detecting forgery using an anti-Stokes material formed on the bill.

Referring to FIG. 7, as the banknote 401 in which the anti-stoke material is formed is inserted into a specific region 405, the input sensor 420, the light emitting modules 430, and the light receiving modules 440 corresponding thereto. 442 may be transferred to the provided position.

As the banknote is transferred, the position of the light receiving module 440 may correspond to the specific region 405 of the banknote 401 in which the anti-stoke material is formed, as shown in FIG. 8.

In this case, the output of each of the

light receiving modules

440 and 442 may be as shown in FIG. 9.

That is, FIG. 9A illustrates a value of sequentially storing the output of the light receiving module 442 corresponding to the position where the anti-stoke material is not formed in the banknote 401. The output of the light receiving module 442 is illustrated in FIG. Can keep the value below the set value (eg, 100).

Meanwhile, FIG. 9B illustrates a value of sequentially storing the output of the light receiving module 440 corresponding to the position where the anti-stoke material is formed in the banknote 401. The output of the light receiving module 440 is constant. The time interval may have a value greater than or equal to a set value (eg, 100).

Hereinafter, with reference to FIGS. 10 to 17, embodiments of a method of detecting the anti-stoke material formed on the banknote by the banknote processing apparatus 10 according to the present invention will be described in more detail.

As described above, the anti-stoke material formed on the banknote may absorb infrared light emitted from the light emitting unit 250 and may emit light having a higher energy (or lower wavelength) than the absorbed infrared light.

However, since the infrared light is absorbed by the anti-stoke material, the time for which the energy (or lower wavelength) of light is emitted is very short (for example, 10 ^-8 seconds), and thus emitted from the anti-stoke material. There is a difficulty in detecting the light.

According to one embodiment of the present invention, the counterfeit judging unit 270 of the banknote processing apparatus 10 detects the presence or absence of an anti-stalk substance formed on the banknote by using the integral value of the light detection signal output from the light receiving unit 260. By judging, it is possible to recognize whether the banknote is forged more easily and accurately.

FIG. 10 is a block diagram illustrating a configuration for detecting an anti-stokes material and an embodiment of the configuration of the counterfeit determination unit 270 illustrated in FIG. 2.

Referring to FIG. 10, the counterfeit determination unit 270 may include a first amplifier 1010, an integrator 1020, a second amplifier 1030, and a recognition unit 1040.

The first amplifier 1010 amplifies the photodetection signal output from the light receiving unit 260, and the integrator 1020 integrates the photodetection signal amplified by the first amplifier 1010 with respect to time to correspond to the integral value. Can output a signal.

The second amplifier 1020 may amplify the signal output from the integrator 1020 to a size recognizable by the recognition unit 1040 and then output the signal to the recognition unit 1040.

FIG. 11 is a graph illustrating a method of detecting the presence or absence of an anti-stalk material by using an output signal of the light receiver, and illustrates a signal input from the second amplifier 1020 to the recognition unit 1040. An example is shown.

(A) of FIG. 11 shows the signal waveform when the anti-stoke phenomenon does not occur (for example, when an anti-stoke substance is not formed in a banknote), and FIG. 11 (b) shows the anti-stalk. The signal waveform is shown when a phenomenon occurs (for example, when anti-stoke material is formed in a banknote).

Referring to FIG. 11A, when the LED provided in the light emitting unit 250 is turned on for a predetermined time t1 and then turned off, the transition phenomenon caused by the anti-stoke material does not occur, and thus the LED is turned off. After that, a specific waveform signal having a voltage higher than a reference value may not be detected.

On the other hand, referring to Figure 11 (b), a transition phenomenon caused by the anti-stock material formed on the bill occurs, the specific waveform signal (A) having a voltage higher than the reference value for a predetermined time after the LED is turned off can be detected. have.

Meanwhile, the waveform signal after the LED is turned off, as shown in FIG. 11B, is a time-integrated value by the integrator 1020, and is easily detected for a longer time than the light detected by the actual light receiving unit 260. Can be.

For the operation as described above, the light emitting unit 250 may have a circuit configuration as shown in FIG. 12 to periodically turn on and off the LED emitting infrared light.

On the other hand, the light receiving unit 260 has a circuit configuration as shown in Figure 13, it can detect the light emitted from the bill and output a signal having a voltage (or current) corresponding to its magnitude.

FIG. 14 is a circuit diagram showing an embodiment of the configuration of the first amplifier shown in FIG. 10, and FIG. 15 is a circuit diagram showing an embodiment of the configuration of the integrator shown in FIG.

14 and 15, when the voltage of the light detection signal output from the light receiving unit 260 is increased by using a diode (for example, in the optical sensor provided in the light receiving unit 260). Energy is measured), and the integrator 1020 may output an integrated value of the signal amplified by the first amplifier 1010 when the voltage of the light detection signal rises. .

Meanwhile, the above operation of the integrator 1020 may be controlled by a circuit having a configuration as shown in FIG. 16.

FIG. 17 is a circuit diagram illustrating an embodiment of the configuration of the second amplifier illustrated in FIG. 10.

The signal amplified by the second amplifying unit 1030 is input to the recognition unit 1040, the recognition unit 1040 determines the presence or absence of the anti-stalk material formed on the bill by the method described with reference to FIG. can do.

At least some of the above-described counterfeit detection methods according to the present invention may be stored in a computer-readable recording medium that is produced as a program for execution in a computer. Examples of the computer-readable recording medium may include ROM, RAM, CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, and the like, and also include those implemented in the form of carrier waves (eg, transmission over the Internet).

The computer readable recording medium can be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, codes, and code segments for implementing the method can be easily inferred by programmers in the art to which the present invention belongs.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

Claims

In the banknote processing apparatus which can detect a counterfeit banknote,

A bill input unit receiving one or more bills;

A transfer unit for transferring the inserted banknotes;

A light emitting unit for irradiating infrared light onto the banknote conveyed by the conveying unit by using a light emitting diode (LED) emitting infrared light;

A light receiving unit for detecting light emitted from the anti-Stokes material formed on the banknote by the irradiated infrared light; And

Banknote processing apparatus including a counterfeit determination unit for determining whether the banknote forgery using the light detected through the light receiving unit.
The method of claim 1, wherein the anti-stoke material formed on the banknote

The banknote processing apparatus which absorbs the infrared light irradiated from the said light emission part, and emits visible light which is higher in energy than the said infrared light.
The method of claim 1, wherein the anti-stoke material formed on the banknote

The banknote processing apparatus which absorbs the infrared light irradiated from the said light emission part, and emits visible light with a wavelength lower than the said infrared light.
The method of claim 1, wherein the light emitting unit

Banknote processing apparatus for irradiating the infrared light to a region on which the anti-Stokes material is formed of one side of the bill to be transferred.
The method of claim 1, wherein the light emitting unit

Banknote processing apparatus for emitting infrared light having a wavelength of 930nm to 1040nm.
The method of claim 1, wherein the light emitting unit

Banknote processing apparatus comprising a convex lens for diffusing the infrared light.
The method of claim 1, wherein the light receiving unit

A visible light filter for filtering light having a wavelength of 380 nm to 800 nm; And

Banknote processing apparatus comprising a light receiving sensor for receiving the light filtered through the visible light filter.
The method of claim 1, wherein the light receiving unit

The banknote processing apparatus located on the opposite side to the said light emitting part with the said banknote interposed so that the light which transmitted the said banknote can be detected.
The method of claim 1, wherein the light receiving unit

The banknote processing apparatus located in the same side as the said light emitting part with respect to the said banknote so that the light emitted from the said banknote can be detected.
The method of claim 1, wherein the counterfeit determination unit

Banknote processing apparatus for determining whether the bill forgery based on the voltage or current corresponding to the size of the light detected through the light receiving unit.
The method of claim 10, wherein the counterfeit determination unit

And a bill processing apparatus for determining whether an anti-stoke material is formed on the bill based on the light detected through the light receiver for a predetermined time after the infrared light is irradiated from the light emitter.
The method of claim 1, wherein the counterfeit determination unit

Banknote processing apparatus including an integrator for outputting the integral value for the light detection signal output from the light receiving unit.
The method of claim 12, wherein the counterfeit determination unit

Further comprising a first amplifier for amplifying the light detection signal output from the light receiving unit,

The banknote processing apparatus which inputs the optical detection signal amplified by the said 1st amplifier to the integrator.
The method of claim 13, wherein the first amplifier

The banknote processing apparatus which amplifies the said photodetection signal only when the voltage of the photodetection signal output from the said light receiving part rises.
The method of claim 12, wherein the counterfeit determination unit

A second amplifier for amplifying a signal output from the integrator; And

And a recognizer that determines whether the banknote is forged, based on a voltage level of the signal output from the second amplifier.
The method of claim 1,

The light emitting unit periodically turns on and off the LED,

And the counterfeit judging unit judges that an anti-stoke material is formed in the bill when the magnitude of light detected by the light-receiving unit is greater than or equal to a reference value after the LED of the light-emitting unit is turned off.
In the method of detecting a counterfeit bill in a bill processing apparatus,

Receiving one or more bills;

Sequentially transferring the inserted bills;

Irradiating infrared light onto at least one surface of the bill to be transferred using an LED emitting infrared light;

Detecting light emitted from the anti-stoke material formed on the banknote by the irradiated infrared light; And

Determining whether the banknote is forged using the detected size of light;

The anti stokes material formed on the banknote

And absorbing the irradiated infrared light and then emitting visible light having a wavelength lower than that of the infrared light.
The method of claim 17, wherein the irradiated infrared light

A falsehood detection method having a wavelength of 930 nm to 1040 nm.
The method of claim 17,

LEDs emitting the infrared rays are periodically turned on and off,

And the anti-stalk material is formed in the banknote when the magnitude of the detected light is greater than a reference value after the LED is turned off.
18. The method of claim 17, wherein determining whether the forgery is

Counterfeit detection method for determining whether the banknote forgery using the time integration value for the size of the detected light.