KR20230081161A - Near-infrared absorbent detection system and measurement method using the same - Google Patents

Abstract

In the present invention, a light source having a peak wavelength of 700 to 1500 nm is irradiated to an area of the surface of a printed matter on which a sample for detecting forgery is applied or not applied, and a light source having the peak wavelength range to be measured is 4 A light source unit including more than 10 and less than 10; a light detecting unit that senses a light source reflected by one area of the surface of the print without configuring a separate optical filter; and a detecting unit configured to measure reflectance of one area of the surface of the printed material and determine whether or not a sample is included or not.

Description

Near-infrared absorbent detection system and measurement method using the same

The present invention relates to a near-infrared absorber detection system and a measurement method using the same. a light source unit including 4 or more and 10 or less light sources having the peak wavelength range to be irradiated and measured; a light detecting unit that senses a light source reflected by one area of the surface of the print without configuring a separate optical filter; and a near-infrared absorber detection system including a detection unit for determining whether a sample is included or authentic by measuring reflectance of one region of the surface of the printed matter, and a measurement method using the same.

With the widespread spread of high-performance color copiers and printers, counterfeiting of banknotes has become easier than in the past, and counterfeiting crimes are increasing, causing great social controversy. Since counterfeit bills by color copiers or color printers are elaborately manufactured, it is very difficult to detect counterfeits with the naked eye. Therefore, counterfeit bills were circulated in the market for a long time and only after they entered the bank, were they identified as counterfeit, and accordingly, in most cases, the holder of the counterfeit bill suffered financial damage.

The wavelength that can be absorbed by the existing light absorber applied to banknotes, industrial logos, etc. was 1000 nm or less. There is a situation.

Therefore, in order to prevent sophisticated counterfeiting crimes as described above, manufacturing of ink having a maximum absorption at 1000 nm or more is required, and the need for developing a detector for detecting this is also increasing.

In accordance with the need for the development of the detector, the present invention is to provide a near-infrared absorber detection system capable of detecting the authenticity of banknotes or industrial logos using a near-infrared light source of 1000 nm or more and an ink exhibiting a maximum absorption wavelength in the range of 1000 nm or more. There is a purpose.

In order to achieve the above object, in one embodiment of the present invention, a light source having a peak wavelength (P) of 700 to 1500 nm is irradiated to one area of the surface of a printed matter on which a sample for detecting forgery is applied or not applied. and a light source unit including 4 or more and 10 or less light sources having the peak wavelength (P) range to be measured; a light detecting unit that detects a light source reflected by one area of the surface of the print without configuring a separate optical filter; and a detecting unit configured to measure reflectance of one area of the surface of the printed material and determine whether or not a sample is included or not.

As an embodiment of the present invention, the wavelength (λ) of the spectrum of each of the 4 to 10 light sources may satisfy P-50≤λ≤P+50 [nm].

As an embodiment of the present invention, the wavelength (λ) of the spectrum of each light source may be in a range that does not overlap with each other.

As an embodiment of the present invention, the sample of the NIR absorber detection system may be a pigment capable of absorbing a light source having a peak wavelength (P) of 1000 nm or more.

As an embodiment of the present invention, the light source detected by the photodetector of the NIR absorber detection system may be a light source having a peak wavelength (P) of 1000 to 1500 nm.

As an embodiment of the present invention, the light source unit of the NIR absorber detection system may be at least one of a light emitting diode and a laser diode.

As an embodiment of the present invention, the detection unit of the near-infrared absorber detection system compares the reflectance measurement value in one area of the printed matter to which the sample is applied with the reflectance in one area of the printed matter to which the sample is applied as a reference value to detect the sample inclusion can be determined.

As an embodiment of the present invention, the near-infrared absorber detection system may further include a display unit for displaying whether or not the sample determined by the detection unit is included.

As an embodiment of the present invention, a method for measuring a sample using a near-infrared absorber detection system includes a light source having a peak wavelength (P) of 700 to 1500 nm on a region of the surface of a printout on which a sample for detecting forgery is not coated. Step of measuring the reflectance by irradiation and storing it as a reference value; Measuring reflectance by irradiating a light source having a peak wavelength (P) of 700 to 1500 nm on one area of the surface of the printed matter on which the sample for detecting forgery is applied; and determining authenticity by comparing the stored reference value with the reflectance of the print to which the sample is applied.

The present invention provides a near-infrared absorber detection system 10 capable of detecting the authenticity of a banknote or industrial logo using a near-infrared light source of 1000 nm or more and an ink exhibiting a maximum absorption wavelength in the range of 1000 nm or more, and a measurement method using the same, Compared to anti-counterfeiting technology that absorbs wavelengths of 1000 nm or less to determine authenticity, there is an effect of more accurately determining authenticity of the printed matter 11.

1 is a configuration diagram of a near-infrared absorber detection system 10.
2 is a diagram showing the result of measuring the reflectance for each wavelength according to the coating rate of the near-infrared absorber by the detector.

In the present invention, the peak wavelength (P) is a single wavelength at which the radiation emission spectrum of the light source reaches the maximum value, and the emission bandwidth is defined as the difference between the upper limit and the lower limit of the wavelength at which the emission spectrum of each light source appears.

As shown in FIG. 1, in the near-infrared absorber detection system 10 of the present invention, a sample for detecting forgery is applied to the surface, or a peak of 700 to 1500 nm in one area of the surface of the printed matter 11 that is not coated. A light source unit 12 that irradiates a light source having a wavelength (P) and includes 4 or more and 10 or less light sources having the peak wavelength (P) range to be measured; a light detecting unit 13 that senses a light source reflected by one area of the surface of the print without configuring a separate optical filter; and a detecting unit 14 for determining whether a sample is included or authentic by measuring reflectance of a region of the surface of the print.

The light source unit 12 of the NIR absorber detection system 10 may use at least one of a light emitting diode and a laser diode.

The sample for detecting whether the NIR absorber detection system 10 is counterfeit may be a pigment capable of absorbing a light source having a peak wavelength (P) of 1000 nm or more, and the light source detected by the photodetector 13 has a peak wavelength ( P) may be 1000 to 1500 nm.

As described above, by including a pigment capable of absorbing a light source having a peak wavelength (P) of 1000 nm or more in the printed material 11 and setting the range of the peak wavelength (P) to be detected to 1000 to 1500 nm, the peak wavelength (P) is 400 nm. Compared to the prior art of detecting a sample that absorbs a light source in the visible ray region of ~700 nm to determine whether it is counterfeit, the sample can be detected in the near-infrared region with a peak wavelength (P) of 1000 nm or more, which can further improve the security of printed materials. there is.

In the light source unit 12 of the NIR absorber detection system 10 , a light source irradiated to a region of the surface of the printed material 11 may be of a different type according to a peak wavelength P.

The light source unit 12 of the near-infrared absorber detection system 10 may irradiate light sources having four or more different peak wavelengths (P) to one area of the surface of the printed matter 11, but four or more and ten or less light sources. It is preferable to irradiate light sources having different peak wavelengths (P).

As described above, since light sources having different peak wavelengths (P) may be irradiated, wavelengths of various ranges corresponding to a wavelength range from visible light to near infrared may be irradiated.

The wavelength (λ) of the spectrum of each of the 4 or more and 10 or less light sources may be P-50≤λ≤P+50 [nm], and the wavelength (λ) of the spectrum of each light source is within the above range. If it is out of range, the wavelengths of a plurality of light sources overlap, making it difficult to accurately measure, and the wavelength (λ) band of the spectrum is too wide, making it difficult to accurately measure at a specific wavelength.

In one embodiment of the present invention, the light source unit 12 may irradiate light sources having peak wavelengths P of 765 nm, 870 nm, 975 nm, and 1080 nm, respectively. λ) is 715≤λ≤815 [nm], the spectrum of a light source with a peak wavelength (P) of 870 nm is 815≤λ≤920 [nm], and the spectrum of a light source with a peak wavelength (P) of 975 nm is 925 ≤λ≤1025 [nm], the spectrum of a light source having a peak wavelength (P) of 1080 nm may be 1030≤λ≤1130 [nm].

As described above, the wavelength (λ) of the spectrum of each light source is set to be in a range that does not overlap with each other, so that it is possible to solve the problem of overlapping wavelengths of a plurality of light sources and making accurate measurement difficult.

In the near-infrared absorber detection system 10 of the present invention, when light sources of different wavelengths are irradiated from the light source unit 12 to the surface of printed matter having different coating rates (absorption printing area ratios), the display unit 16 measures the difference in reflectance. Information can be provided by making data or graphing.

When the coating rate information is applied to a printed matter containing the same sample, almost similar reflectance results can be obtained, and through this result, it is possible to identify printed matter information or a unique printing material.

In other words, since it shows that the presence or absence of a sample can be accurately derived by irradiating light having a wavelength range of 1000 nm or less or more, it means that it is possible to precisely determine whether a printed matter is forged.

The light detection unit 13 of the NIR absorber detection system 10 may detect a light source reflected by a region of the surface of the print without configuring a separate optical filter.

In general, when a light source is irradiated from the light source unit 12 in the photodetector, only a certain wavelength range of the light source of a special wavelength emitted from the sample of the printed material is filtered to pass, and the filters used include a long pass filter, a low pass filter, and a band A pass filter, a pre-selector, and the like can be used.

The filter may serve to select a wavelength of a specific emission region by selectively transmitting a part of the spectrum of a single light source and blocking the rest.

In the present invention, the light sensing unit 13 in the near infrared absorber detection system 10 may measure the amount of light reflected from the light source unit using an optical element capable of detecting a near infrared region including visible light. At this time, the light of the light source is sequentially irradiated without applying a separate optical filter for detection, and the light corresponding to the wavelength of each light source can be received and applied as a reflectance measurement value.

Portability can be improved by simplifying the equipment structure by including only an optical element having a relatively simple structure capable of detecting the near-infrared region without having a separate filter as described above.

The near-infrared absorber detection system 10 may include a reference value storage unit 15, which includes a reference value of reflectance in a region of a printed material 11 to which a sample is not applied or a white paper, a printed material to which a sample is applied 11 ) may store a reflectance reference value in one region.

To measure the reflectance, the reflectance of the same paper that is not coated first is measured, the result is stored, the reflectance is measured in one area of the target printed matter 11 applied, and the difference between the measured values is calculated to determine the wavelength range of each light source. derive the reflectance.

The measured reflectance value obtained by measuring one area of the print 11 to which the sample is applied may be compared with the previously stored reflectance reference value in the detection unit 14 to derive corrected data. Calibration uses the measurement data of the standard measuring instrument to adjust the result so that the same result as the measurement result of the absorbent material can be displayed.

The corrected data is compared again with the reflectance reference value in one area of the printed material 11 to which the sample is not applied or the same type of paper that is not printed, and finally, the detection unit 14 can determine whether or not the sample is included. .

The near-infrared absorber detection system 10 may express whether or not the sample determined by the detection unit 14 is included through the display unit 16, and may further include information on the wavelength for display, and the display unit 16 The authenticity displayed on may be transmitted to the smart device through a short-range communication means.

The near-infrared absorber detection system 10 may further include the control unit 17, wherein the control unit 17 is a zero button pressed when measuring a reference value on the same kind of unprinted paper or a portion where the absorber is not applied, It may include a measurement button that is pressed when moving to an area where the absorber is applied and measuring a reference value.

In the method of measuring a sample using the near-infrared absorber detection system 10, a light source having a peak wavelength (P) of 700 to 1500 nm is irradiated to an area of the surface of a printout on which a sample for detecting forgery is not applied, and the reflectance is measured. and storing it as a reference value; Measuring reflectance by irradiating a light source having a peak wavelength (P) of 700 to 1500 nm on one area of the surface of the printed matter on which the sample for detecting forgery is applied; and determining authenticity by comparing the stored reference value with the reflectance of the print to which the sample is applied.

Preparation Example: Preparation of samples coated with absorbents in different area ranges

Sample 1 was prepared by applying an absorber capable of absorbing near-infrared rays in the range of 1000 nm peak wavelength (P) to the entire surface of the printed material (100% of the coating area).

Samples 2 to 5 are sequentially prepared by applying an absorbent capable of absorbing near-infrared rays in the range of 1000 nm peak wavelength (P) so that the application area is 80%, 60%, 40%, and 20%, respectively, based on the entire surface of the printed material. did

Experimental Example: Measurement of reflectance for each wavelength of samples coated with different thicknesses of absorbers

The reflectance according to the wavelength was measured for samples 1 to 6 prepared in the above preparation example through a near-infrared absorber detector manufactured by Genicom, respectively. The measurement method is as follows.

1. Pressing the zero button on the control panel of the sensor and measuring the white paper or the area where no absorbent was applied by pressing the measurement button.

2. After moving the light source of the device to the area where the absorber was applied in the sample, the measurement button was pressed.

3. LEDs having different peak wavelengths (P) of 765 nm, 810 nm, 935 nm, and 1070 nm were sequentially emitted from the light source to examine the measurement area.

4. The reflectance was measured and stored from the LEDs of each wavelength using an optical detector.

5. Authenticity was determined using the stored reflectance as a reference value and absorber characteristic values stored at the time of manufacturing the device, and the judgment result was displayed using a display device.

6. The judgment result was transmitted to a smart phone using Bluetooth and displayed as a graph.

2 is a diagram showing the result of measuring the reflectance for each wavelength according to the coating rate of the near-infrared absorber by the detector.

As described above, in the present invention, when light sources of different wavelengths are irradiated on the surface of printed matter having different coating rates (absorption printing area ratios), the display unit 16 converts the difference in reflectance into data or graphs to provide information.

When the coating rate information is applied to a printed matter containing the same sample, almost similar reflectance results can be obtained, and through this result, it is possible to identify printed matter information or a unique printing material.

10: NIR absorber detection system
11: printout
12: light source
13: light detection unit
14: detection unit
15: reference value storage unit
16: display
17: control panel

Claims (9)

A sample for detecting forgery is applied to the surface or a light source having a peak wavelength (P) of 700 to 1500 nm is irradiated to an area of the surface of the printed matter that is not coated, and the peak wavelength (P) to be measured is A light source unit including 4 or more and 10 or less light sources;
a light detecting unit that detects a light source reflected by one area of the surface of the print without configuring a separate optical filter; and
A near-infrared absorber detection system comprising a detection unit for determining whether a sample is included or genuine by measuring reflectance of one region of the surface of the printed material. According to claim 1,
The wavelength (λ) of the spectrum of each of the four or more and ten or less light sources satisfies P-50≤λ≤P+50 [nm]. According to claim 2,
The near-infrared absorber detection system, characterized in that the wavelength (λ) of the spectrum of each light source is in a range that does not overlap with each other. According to claim 1,
The sample is a near-infrared absorber detection system, characterized in that the pigment capable of absorbing a light source having a peak wavelength (P) of 1000 nm or more. According to claim 1,
The light source detected by the photodetector is a near-infrared absorber detection system, characterized in that the light source having a peak wavelength (P) of 1000 ~ 1500nm. According to claim 1,
The light source unit is a near-infrared absorber detection system, characterized in that at least one of a light emitting diode or a laser diode. According to claim 1,
The detection unit determines whether the sample is included by comparing the reflectance measurement value in one area of the printed matter to which the sample is applied with the reflectance in one area of the printed matter to which the sample is applied as a reference value. According to claim 1,
A near-infrared absorber detection system further comprising a display unit for displaying whether or not the sample determined by the detection unit is included. A step of irradiating a light source having a peak wavelength (P) of 700 to 1500 nm to an area of the surface of the printed matter on which a sample for detecting forgery is not applied, measuring reflectance and storing it as a reference value;
Measuring reflectance by irradiating a light source having a peak wavelength (P) of 700 to 1500 nm on one area of the surface of the printed matter on which the sample for detecting forgery is applied; and
A method of measuring a sample using a near-infrared absorber detection system comprising the step of determining authenticity by comparing the stored reference value with the reflectance of a printed matter to which the sample is applied.

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