JPH1186074A - Genuineness discriminating device for paper sheets - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make easily decidable whether or not paper sheets are genuine without requiring any skilled operator and comparing it with a sample by making a genuine paper money show an image having a specific pattern while forged paper money shows an image entirely similar to that viewed with the naked eye or a white image. SOLUTION: On the basis of image data to wavelength obtained by a 1st area sensor 60 and image data to wavelength obtained by a 2nd area sensor 80, an image drawn in special ink is extracted. Namely, This device outputs a TV signal having the white and black of the pattern of the money A inverted and the part of the face painted out in black from a video circuit 91 for the genuine paper money which is printed by using the special ink for the part of the face and general ink for other parts. Further, a TV signal of the pattern of the money A is outputted from a video circuit 91. Then those TV signals are put one over the other by a signal level adding circuit 94 and an image of only the face part is displayed in a display window.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an authenticity discriminating apparatus for discriminating the authenticity of paper sheets such as banknotes, stamps, and securities.

[0002]

2. Description of the Related Art A conventional paper authenticity discriminating apparatus includes a light illuminating section for illuminating a sheet with infrared light, an infrared camera for photographing a sheet under illumination of the light illuminating section, and an infrared camera. And a television monitor for displaying the displayed video. Then, the operator observes the image photographed by the infrared camera on a television monitor, and identifies the authenticity of the paper sheet.

In other words, since genuine paper sheets are printed with a special ink having different reflectances for visible light and infrared light, illuminating the paper sheets with infrared light has a different pattern from that under visible light. The pattern appears on the surface of the paper. On the other hand, forged paper sheets are printed with general ink, which has almost the same reflectance for visible light and infrared light. It is not different from the pattern. For this reason, the authenticity of the paper sheet can be determined by checking on the television monitor whether a different pattern appears on the surface of the paper sheet illuminated with infrared light.

[0004]

However, in the conventional paper sheet authenticity discriminating apparatus, the pattern of the sheet surface under visible light and the pattern of the sheet surface under infrared light are only partially. If not, it was difficult to spot these differences. For this reason, a skilled operator has to make a determination, or have to make a determination by comparing a sample printed with a pattern on the surface of a paper sheet with a sample displayed on a television monitor at hand. .

The present invention solves such a problem, and does not require a skilled operator, and can easily determine the authenticity of a sheet without comparing it with a sample. The purpose is to provide.

[0006]

In order to solve the above-mentioned problems, a paper sheet authenticity discriminating apparatus according to the present invention has a reflectance for a first wavelength and a reflectance for a second wavelength different from the first wavelength. Genuine paper printed with a general ink and a special ink having a reflectance similar to that of the general ink for the first wavelength and having a different reflectance from that of the general ink for the second wavelength And a paper sheet authenticity discriminating apparatus for discriminating a counterfeit paper sheet printed with one of a general ink and a special ink, wherein a first wavelength illuminating the paper sheet with light of a first wavelength. An illuminating unit, a second illuminating unit for illuminating the paper sheet with the light of the second wavelength, a first area sensor having sensitivity to the first wavelength, and an image formed by the light reflected by the paper sheet. Imaging means for imaging a paper sheet including a first imaging optical system for forming an image on an area sensor The image formed by light reflected by the second area sensor and paper sheet having a sensitivity to the second wavelength second
A second imaging unit that includes a second imaging optical system that forms an image on the area sensor, and an image capturing unit that captures an image of a sheet, image data corresponding to a first wavelength obtained by the first area sensor, and a second area The image processing apparatus further includes: an image extracting unit that extracts an image drawn with the special ink based on image data for the second wavelength obtained by the sensor, and a display unit that displays the image extracted by the image extracting unit. And

[0007] When such a configuration is adopted, the paper sheet is composed of the light of the first wavelength emitted from the first lighting means and the light of the second wavelength emitted from the second lighting means. Illuminated. The light reflected by the paper sheet by these illuminations is incident on the first imaging optical system and the second imaging optical system, and an image formed by the incident light is transmitted to the first area sensor and the second area sensor. Each is imaged. Since the first area sensor has sensitivity to the first wavelength, an image of a sheet by light of the first wavelength emitted from the first illuminating means is captured from the first area sensor. Further, since the second area sensor has sensitivity to the second wavelength, the image of the paper sheet by the light of the second wavelength emitted from the second illuminating means is formed by the second area sensor.
Are imaged by the area sensor. That is, image data for the first wavelength is obtained from the first area sensor by imaging, and image data for the second wavelength is obtained from the second area sensor.

[0008] Here, the portion of the surface of the sheet printed with general ink is obtained by the first area sensor because the reflectance for the first wavelength and the reflectance for the second wavelength are similar. The image data is substantially equal to the image data obtained by the second area sensor. On the other hand, in the portion printed with the special ink, the reflectance for the first wavelength is similar to that of the general ink and the reflectance for the second wavelength is different from that of the general ink. The obtained image data is different from the image data obtained by the second area sensor. Therefore, by using the image data for the first wavelength obtained by the first area sensor and the image data for the second wavelength obtained by the second area sensor, the image data for the first wavelength and the image data for the second wavelength are obtained. The difference from the image data, that is, the image drawn with the special ink can be extracted.

The paper sheet authenticity discriminating apparatus according to the present invention comprises a general ink having a reflectance for a first wavelength and a reflectance for a second wavelength different from the first wavelength, and a general ink for a first wavelength. In the case of the first embodiment, the genuine paper printed with the special ink whose reflectance is similar to that of the general ink and the reflectance is different from that of the general ink for the second wavelength, and printing with one of the general ink and the special ink A paper sheet authenticity discriminating apparatus for discriminating the forged paper sheet, wherein the illuminating means illuminates the paper sheet with light in a wavelength band including a range of the first wavelength and the second wavelength; A first area sensor having sensitivity to one wavelength and a first imaging optical system configured to form an image formed by light reflected by the sheet on the first area sensor; 1 imaging means, a second area sensor having sensitivity to the second wavelength, and paper sheets. A second imaging unit that captures an image of a sheet including a second imaging optical system that forms an image formed by the emitted light on the second area sensor; and a first wavelength that is obtained by the first area sensor. Image extracting means for extracting an image drawn with special ink based on the image data for the second wavelength and the image data for the second wavelength obtained by the second area sensor, and displaying the image extracted by the image extracting means. And a display means.

When such a configuration is adopted, the paper sheet is illuminated with light in a wavelength band including the range of the first wavelength and the second wavelength emitted from the illumination means. The light reflected by the sheet by this illumination is incident on the first imaging optical system and the second imaging optical system, and the images formed by the incident light are respectively transmitted to the first area sensor and the second area sensor. It is imaged. First
Since the area sensor has sensitivity to the first wavelength, an image of a sheet by light of the first wavelength is captured by the first area sensor out of the light emitted from the illumination unit.
In addition, since the second area sensor has sensitivity to the second wavelength, the second area sensor includes the second area sensor out of the light emitted from the illumination unit.
The image of the paper sheet is picked up by the second area sensor. That is, image data for the first wavelength is obtained from the first area sensor by imaging, and image data for the second wavelength is obtained from the second area sensor.

Here, the portion of the surface of the sheet printed with the general ink is obtained by the first area sensor because the reflectance for the first wavelength and the reflectance for the second wavelength are similar. The image data is substantially equal to the image data obtained by the second area sensor. On the other hand, in the portion printed with the special ink, the reflectance for the first wavelength is similar to that of the general ink and the reflectance for the second wavelength is different from that of the general ink. The obtained image data is different from the image data obtained by the second area sensor. Therefore, by using the image data for the first wavelength obtained by the first area sensor and the image data for the second wavelength obtained by the second area sensor, the image data for the first wavelength and the image data for the second wavelength are obtained. The difference from the image data, that is, the image drawn with the special ink can be extracted.

The paper sheet authenticity discriminating apparatus according to the present invention comprises a light branching means for branching light reflected by the sheet in two directions, a first imaging optical system and a second imaging optical system. It may be further provided.

When such a configuration is adopted, an image of a paper sheet is picked up by the first area sensor due to light reflected toward the first imaging optical system. Further, an image of the paper sheet by the light reflected toward the second imaging optical system is captured by the second area sensor.

[0014] The paper sheet authenticity discriminating apparatus according to the present invention is a general ink in which the reflectance for the first wavelength and the reflectance for the second wavelength different from the first wavelength are similar, and the general ink for the first wavelength. In the case of the first embodiment, the genuine paper printed with the special ink whose reflectance is similar to that of the general ink and the reflectance is different from that of the general ink for the second wavelength, and printing with one of the general ink and the special ink A paper sheet authenticity discriminating apparatus for discriminating a printed sheet from a forged paper sheet, comprising: first illuminating means for illuminating the sheet with light of a first wavelength; A paper sheet including a second illuminating means for illuminating, an area sensor having sensitivity to the first wavelength and the second wavelength, and an imaging optical system for forming an image formed by light reflected by the paper sheet on the area sensor; Image pickup means for picking up an image of a class; And and a second frame memory, the first
Illumination switching means for alternately switching between illumination by the illumination means and illumination by the second illumination means; and image data for the first wavelength obtained by the area sensor under illumination by the first illumination means in the first frame memory. The image data for the second wavelength obtained by the area sensor under the illumination by the second illumination means is stored in the second frame memory while being stored. Switching means for switching the frame memory in which the image data is stored, based on the image data for the first wavelength stored in the first frame memory and the image data for the second wavelength stored in the second frame memory Extracting means for extracting an image drawn with special ink, and displaying means for displaying the image extracted by the image extracting means It may be characterized in that it comprises and.

When such a configuration is adopted, the illumination by the first illumination means and the illumination by the second illumination means are alternately switched by the illumination switching means, and the first light emitted from the first illumination means is switched. The light of the wavelength and the light of the second wavelength emitted from the second illumination means are alternately applied to the paper sheet. The light reflected by the paper sheet by this irradiation is incident on the image forming optical system, and an image based on the incident light is formed on the area sensor. The area sensor captures an image of a sheet and obtains image data. Here, since the frame memory in which each image data is stored is switched in synchronization with the switching timing of the illumination switching unit, the image data for the first wavelength obtained under illumination by the first illumination unit is stored in the first frame. Image data for the second wavelength obtained under illumination by the second illumination means and stored in the memory is stored in the second frame memory.

Here, the portion printed with the general ink on the surface of the sheet is obtained by the first area sensor because the reflectance for the first wavelength and the reflectance for the second wavelength are similar. The image data is substantially equal to the image data obtained by the second area sensor. On the other hand, in the portion printed with the special ink, the reflectance for the first wavelength is similar to that of the general ink and the reflectance for the second wavelength is different from that of the general ink. The obtained image data is different from the image data obtained by the second area sensor. Therefore, by using the image data for the first wavelength obtained by the first area sensor and the image data for the second wavelength obtained by the second area sensor, the image data for the first wavelength and the image data for the second wavelength are obtained. The difference from the image data, that is, the image drawn with the special ink can be extracted.

In the paper sheet authenticity discriminating apparatus according to the present invention, the reflectance of the special ink at the second wavelength is larger than the reflectance at the first wavelength, and the image extracting means outputs image data corresponding to the second wavelength. Image inverting means for inverting the black and white level of each pixel, and a superimposed image in which image data for the first wavelength and image data for the second wavelength output from the image data inverting means are superimposed for each pixel. A superimposing means for generating data, wherein an image drawn with special ink is extracted based on the superimposed image data generated by the superimposing means.

Since the reflectance of the general ink at the first wavelength and the reflectance of the special ink at the first wavelength are similar and relatively small, the image data obtained by the first area sensor is Is white, and the part drawn with the general ink and the special ink is image data displayed in black. Further, since the reflectance of the special ink at the second wavelength is higher than the reflectance of the general ink at the second wavelength, the image data obtained by the second area sensor includes the background portion of the paper sheet and the special ink. The image data displayed in white is the image data displayed in black, and the image data displayed in black is displayed in black.

Subsequently, the second image data is inverted by the image data inverting means.
By inverting the black-and-white level of the image data for each pixel for each pixel, the image data output from the image data inverting means is such that the background portion of the paper sheet and the portion drawn with the special ink are black, and the general ink The portion drawn by is the image data displayed in white.

Further, by superimposing the image data for the first wavelength and the image data for the second wavelength outputted from the image data inverting unit for each pixel by the superimposing means, the background portion of the paper sheet and the The part drawn with the general ink is white, and the part drawn with the special ink is black image data, so that the image drawn with the special ink can be extracted.

More specifically, considering that a voltage signal in the range of, for example, 0.0 V (black level) to 0.7 V (white level) is used as the image data, the image data for the first wavelength is considered. When each pixel is compared with the image data for the second wavelength output from the image data inverting means, when both pixels are black, that is, when the voltage signal is 0 V, the pixel value is also superimposed. , The voltage signal is 0
V, that is, black, but one or both pixels are white, that is, when the voltage signal is 0.7 V, and when the pixel values are superimposed, the voltage signal becomes 0.7 V, that is, white. Therefore, in both the image data for the first wavelength and the image data for the second wavelength output from the image data inverting means, only the portion drawn with the special ink displayed in black is extracted. .

[0022] The authenticity identification device for paper sheets of the present invention may be characterized in that the light of the first wavelength and the light of the second wavelength are a combination of visible light and infrared light.

When such a configuration is adopted, the wavelength band of the first wavelength and the wavelength band of the second wavelength do not overlap, so that the image of the part printed with the special ink and the part of the image printed with the general ink are used. And the boundary between the image and the original image becomes clear, and it becomes easy to determine the authentic paper sheet and the counterfeit paper sheet.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a paper sheet authenticity identification apparatus according to the present invention will be described below with reference to the accompanying drawings. In the paper sheet authenticity identification device according to the following embodiment, the reflectance in the visible wavelength range (first wavelength) and the reflectance in the infrared wavelength range (second wavelength different from the first wavelength) are similar. Authentic ink printed with general ink and special ink whose reflectance is similar to that of general ink in the visible wavelength range and whose reflectance is much higher in the infrared wavelength range than that of general ink A paper sheet authenticity discriminating apparatus for identifying paper sheets and counterfeit paper sheets printed with one of the general ink and the special ink.

(First Embodiment) FIG. 1 is a sectional view showing a paper sheet authenticity discriminating apparatus 1 according to a first embodiment. As shown in FIG. 1, the paper sheet authenticity identification device 1 includes a rectangular parallelepiped light-shielding case 10. A display window 11 is provided on an upper plate 10 a of the light-shielding case 10, and a reading window 12 is provided on a lower plate 10 b. I have. A protective glass is fitted in the display window 11 and the reading window 12. A green LED that emits visible light is provided on one side plate 10c inside the light shielding case 10.
(First lighting means) 20 is attached obliquely downward. Also, the other side plate 10 inside the light shielding case 10
An infrared LED (second illuminating means) 30 for irradiating infrared rays is attached to d in a diagonally downward direction. Therefore, the entire surface of the reading window 12 is illuminated with the visible light emitted from the green LED 20 and the infrared light emitted from the infrared LED 30.

Below the display window 11, a video monitor (display means) 40 such as a monochrome liquid crystal panel is provided.
2 can be displayed. Further, a backlight unit 41 is provided below the video monitor 40, and can irradiate the video monitor 40 with light so as to obtain a sufficient contrast. Here, a white fluorescent lamp is used as a light source of the backlight unit 41.

A partition plate 50 suspended from the upper plate 10a is provided below the backlight unit 41, and an area sensor having sensitivity in the visible light band (first area sensor) is provided on the lower surface of the partition plate 50. ) 60 is the sensor surface 60
a and the reading window 12 are opposed to each other. Further, below the area sensor 60, an image forming lens (first image forming optical system) 61 for forming an image formed by light reflected by the reading window 12 on a sensor surface 60a of the area sensor 60 is provided. .

On the optical path between the area sensor 60 and the reading window 12, of the light reflected by the reading window 12, visible light is transmitted and travels straight toward the area sensor 60, and infrared light is reflected. A beam splitter (light splitting means) 70 composed of a dichroic mirror for directing the light toward the side plate 10d is provided. Further, the side plate 10 on the optical path of the light reflected by the beam splitter 70
In d, an area sensor (second area sensor) 80 having sensitivity in the infrared band and an imaging lens (second area sensor) for forming an image formed by light reflected by the beam splitter 70 on the sensor surface 80a of the area sensor 80 And an imaging optical system 81). Here, the imaging lens 61 and the imaging lens 8
1, and the area sensor 60 and the area sensor 80 are provided at symmetrical positions with respect to the beam splitter 70, respectively.

A circuit board 90 is provided on the upper surface of the partition plate 50. As shown in FIG. 2, a video signal (image data) for the visible wavelength range obtained by the area sensor 60 and an area are provided on the circuit board 90. Image circuits 91 and 92 constituting image extracting means for extracting an image drawn with special ink based on an image signal in the infrared wavelength range obtained by the sensor 80, a signal level inverting circuit (image data inverting means) 93 and signal level adding circuit (superimposing means) 9
4 are provided. The video circuit 91 includes the area sensor 6
0, the video signal output from
The video circuit 92 is a circuit that converts a video signal output from the area sensor 80 into a TV signal. The signal level inversion circuit 93 is a circuit that inverts the signal level of the TV signal output from the video circuit 92 for each pixel. Here, inverting the signal level means, for example, 0.0 V
This means inverting the black and white level of a TV signal represented by a voltage signal within a range from (black level) to 0.7 V (white level). More specifically, for example, from 0.0 V (black level)
The signal level represented by xV within the range of 0.7 V (white level) is set to 0.7-xV. Further, the signal level adding circuit 94 is a circuit that superimposes the signal level of the TV signal output from the signal level inverting circuit 93 and the TV signal output from the video circuit 91 for each pixel. Here, the overlapping of the signal levels means, for example, 0.
It means that a larger one of two signal levels expressed in a range of 0 V (black level) to 0.7 V (white level) is taken. For example, if both signal levels are 0.0V
(Black level), the superimposed result is also 0.0V
(Black level), but when both or one of the two signal levels is 0.7 V (white level), the result of superposition is 0.7 V (white level).

In the paper sheet authenticity discriminating apparatus 1, incident light is separated into visible light and infrared light by using a beam splitter 70 composed of a dichroic mirror, but a general beam splitter other than a dichroic mirror is used. Thus, incident light may be divided into two directions without wavelength separation. Also in this case, the area sensor 60 has sensitivity in the visible light band, and the area sensor 80 has sensitivity in the infrared band. An image is taken.

Next, the operation of the paper sheet authenticity discriminating apparatus 1 according to the first embodiment will be described. As shown in FIG.
When the paper sheet authenticity identification device 1 is placed on the banknote (sheets) A and a power switch (not shown) is turned on, the green LED 20 and the infrared LED 30 in FIG.
The bill A is uniformly illuminated with the visible light emitted from the D20 and the infrared light emitted from the infrared LED 30. Banknote A
The light reflected by the beam goes straight upward, and the beam splitter 70
Incident on. Of the light incident on the beam splitter 70, visible light passes through the beam splitter 70 and forms an image on the sensor surface 60 a of the area sensor 60 by the imaging lens 61. Of the light incident on the beam splitter 70, infrared rays are reflected by the beam splitter 70 and form an image on the sensor surface 80 a of the area sensor 80 by the imaging lens 81.

When an image is formed on the sensor surface 60a of the area sensor 60, a video signal of this image is output from the area sensor 60. The video signal output from the area sensor 60 is converted into a TV signal by the video circuit 91 and input to the signal level adding circuit 94. When an image is formed on the sensor surface 80a of the area sensor 80, a video signal of this image is output from the area sensor 80. Area sensor 80
The video signal output from is converted into a TV signal by the video circuit 92 and input to the signal level inversion circuit 93. The signal level of the input TV signal is adjusted by a signal level inverting circuit 9.
3, the signal level is inverted for each pixel.
Is input to

As described above, the signal level adding circuit 94 includes:
TV signal from signal level inverting circuit 93 and video circuit 91
, And the signal levels of these TV signals are superimposed for each pixel. The TV signal superimposed by the signal level adding circuit 94 is output to the video monitor 4
0, and the TV signal is displayed on the display window 11 as an image of the bill A.

Here, since the reflectance of the general ink in the visible wavelength range and the reflectance of the special ink in the infrared wavelength range are similar and relatively small, the video signal output from the area sensor 60 is The background portion of the bill A is white (because the background portion has a high reflectance), and the portion drawn with the general ink and the special ink is a video signal displayed in black. Further, since the reflectance of the special ink in the infrared wavelength range is much larger than that of the general ink in the infrared wavelength range, the area sensor 8
The video signal output from 0 is a video signal in which the background portion of the bill A and the portion drawn with the special ink are white, and the portion drawn with the general ink is displayed in black.

Subsequently, the TV signal output from the video circuit 92 is inverted by the signal level inverting circuit 93 for each pixel, so that the TV signal is converted to the bill A.
The background signal and the portion drawn with the special ink are black, and the portion drawn with the general ink is a white TV signal.

Further, the signal level adding circuit 94
By superimposing the TV signal inverted by the signal level inverting circuit 93 and the TV signal output from the video circuit 91 for each pixel, the background portion of the bill A and the portion drawn with the general ink are white, The portion drawn with ink becomes a black TV signal, and an image drawn with special ink can be extracted. As a result, the portion printed with the special ink is displayed on the display window 11 as a black image.

Here, in the case where the banknote A is a genuine banknote printed using special ink for the face portion and general ink for the other portion, the white and black of the pattern of the banknote A are reversed and the face of the face is inverted. A TV signal whose portion is painted black is output from the signal level inversion circuit 93 (see FIG. 4A). In addition, a TV signal of the pattern of the bill A is output from the video circuit 91 (see FIG. 4B). Then, these TV signals are superimposed by the signal level adding circuit 94, whereby an image of only the face portion is displayed on the display window 11 (FIG. 4).
(C)).

Accordingly, when the authenticity of the banknote A is determined based on the image displayed on the display window 11, only the face of the image of the authentic banknote emerges, so that the authentic banknote can be easily determined. it can. Further, since the image of the counterfeit banknote created by color copying with the ink that reflects infrared rays looks the same as when viewed with the naked eye, it is easy to determine the counterfeit banknote by color copying. Furthermore, since the image of a counterfeit banknote created by monochrome copying with a toner that absorbs infrared rays is entirely white, it is easy to determine a counterfeit banknote by monochrome copying. As described above, the authenticity of the bill A can be easily determined on the basis of the image displayed on the display window 11, so that a skilled operator is not required and there is no need to compare the bill with a sample.

The reason why the amount of light received by the area sensors 60 and 80 due to the light reflected by the general ink portion is substantially equal is that the irradiation amounts of visible light and infrared light are substantially equal and the light reception of the area sensors 60 and 80 is almost equal. This is because the sensitivities are the same. Here, when the irradiation amounts of visible light and infrared light are different, by using the area sensors 60 and 80 having different light receiving sensitivities, the light receiving amounts of the area sensors 60 and 80 can be made substantially equal. Also, the area sensor 6
Even when the light receiving sensitivities of 0 and 80 are different, the area sensor 60,
80 can be made substantially equal to the amount of received light. Further, in the configuration according to the above embodiment, since the imaging lens 61 and the imaging lens 81 and the area sensor 60 and the area sensor 80 are provided at symmetrical positions with respect to the beam splitter 70, respectively. It is not necessary to consider a problem such as a position shift at the time of superimposing images, and highly accurate true / false judgment can be performed.

(Second Embodiment) Next, a paper sheet authenticity identification device 2 according to a second embodiment will be described. FIG. 5 is a cross-sectional view illustrating the paper sheet authenticity identification device 2. Also, FIG.
FIG. 2 is a block diagram illustrating an internal configuration of a paper sheet authenticity identification device 2. The second embodiment is different from the first embodiment shown in FIG. 1 in that instead of the green LED 20 and the infrared LED 30, a light source that emits light in a wavelength band including a range of visible light and infrared light ( (Illumination means) 100. Other configurations are the same as or equivalent to the first embodiment. Note that the same or equivalent components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 5 and FIG.
The light source 100 is attached obliquely downward to one side plate 10c inside the banknote 0, and the bill A is uniformly illuminated by the light emitted from the light source 100. The light reflected by the bill A travels straight upward and is separated into visible light and infrared light by the beam splitter 70. The visible light enters the area sensor 60 and the infrared light enters the area sensor 80, and the area sensors 60 and 80 output video signals. The video signal output from the area sensor 60 is converted into a TV signal by a video circuit 91,
4 is input. Also, the sensor surface 8 of the area sensor 80
When an image is formed on 0a, a video signal of this image is output from the area sensor 80. The video signal output from the area sensor 80 is converted into a TV signal by a video circuit 92,
The signal is input to the signal level inversion circuit 93. TV input
The signal level of the signal is inverted for each pixel by a signal level inverting circuit 93 and input to a signal level adding circuit 94.

As described above, the signal level adding circuit 94 includes:
TV signal from signal level inverting circuit 93 and video circuit 91
, And the signal levels of these TV signals are superimposed for each pixel. The TV signal superimposed by the signal level adding circuit 94 is output to the video monitor 4
0, and the TV signal is displayed on the display window 11 as an image of the bill A.

As described above, when the banknote A is a counterfeit banknote, an image similar to the entire surface as seen by the naked eye or an image of the entire surface is displayed in the display window 11 and the banknote A is a genuine banknote. , An image of only the face portion is displayed on the display window 11. Therefore, when the authenticity of the banknote A is determined based on the image displayed on the display window 11, since only the face portion of the image of the authentic banknote emerges, the authentic banknote can be easily determined. Further, since the image of the counterfeit banknote created by color copying with the ink that reflects infrared rays looks the same as when viewed with the naked eye, it is easy to determine the counterfeit banknote by color copying. Furthermore, since the image of a counterfeit banknote created by monochrome copying with a toner that absorbs infrared rays is entirely white, it is easy to determine a counterfeit banknote by monochrome copying. As described above, the authenticity of the bill A can be easily determined on the basis of the image displayed on the display window 11, and thus does not require a skilled operator.
And there is no need to compare with the sample.

(Third Embodiment) Next, a paper sheet authenticity discriminating apparatus 3 according to a third embodiment will be described. FIG. 7 is a cross-sectional view illustrating the paper sheet authenticity identification device 3. Also, FIG.
FIG. 2 is a block diagram illustrating a configuration of a paper sheet authenticity identification device 3.
The third embodiment differs from the first embodiment shown in FIG. 1 in that the third embodiment does not include a beam splitter 70, an area sensor 80, an imaging lens 81, and a video circuit 92.
An area sensor 110 having sensitivity to visible and infrared wavelengths is provided in place of the area sensor 60, and an illumination switching circuit (illumination switching means) 120 and a video switching circuit (switching means) 130 are provided on the circuit board 90. Points that have been
The point is that frame memories 140 and 150 for inputting a video signal from the video switching circuit 130 are provided. Other configurations are the same as or equivalent to the first embodiment.
Note that the same or equivalent components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 7 and FIG.
Output a TV synchronization signal, and the TV synchronization signal is input to the illumination switching circuit 120 and the video switching circuit 130 in parallel. The TV synchronization signal is a TV signal converted by the video circuit 91.
In the field scan of the signal, a first switch pulse is generated every field scan of an even scan line, and a second switch pulse is generated every field scan of an odd scan line.
The illumination switching circuit 120 alternately switches the power supply destination from the illumination power supply 160 between the green LED 20 and the infrared LED 30 at the timing of these switching pulses. That is, at the timing of the first switching pulse, the green LE
Power is supplied to D20, and power is supplied to the infrared LED 30 at the timing of the second switching pulse. Here, the field scan of the TV synchronization signal is performed 60 times per second, so that the green LED 20 and the infrared LED 30 are three times per second.
Lights up 0 times at a time.

As described above, the green LED 20 and the infrared LED
When the lamps 30 and 30 are alternately turned on, the bill A is uniformly illuminated with the visible light emitted from the green LED 20 and the infrared light emitted from the infrared LED 30. The light reflected by the bill A is incident on the area sensor 110, and the area sensor 110 outputs a video signal.

Here, the area sensor 110 is a so-called frame interline transfer type CCD and includes a photosensitive section, a vertical transfer section, a storage section, a horizontal transfer path, and an output section. For this reason, in the area sensor 110, when the visible light is first turned on and the photosensitive unit receives the light, the electric charge is immediately transferred to the storage unit immediately at the timing of the vertical synchronization signal indicating the switching. Subsequently, while the infrared light source is turned on and the photosensitive section receives the light, the electric charge at the time of visible light accumulated in the accumulation section is output from the output section via the horizontal transfer path. Further, while the visible light is turned on again according to the next vertical synchronization signal and the photosensitive portion is receiving the light, the operation of similarly transferring the charge at the time of infrared light accumulated in the accumulation portion and outputting the same is repeated. .

The video signal output from the area sensor 110 is converted into a TV signal by the video circuit 91 and input to the video switching circuit 130. Similarly to the illumination switching circuit 120, the video switching circuit 130 switches the memory for inputting the TV signal between the frame memory 140 and the frame memory 150 at the timing of each switching pulse of the TV synchronization signal.

That is, the TV signal output from the video circuit 91 is input to the frame memory 140 at the timing of the first switching pulse for turning on the green LED 20. Then, the signal level of the TV signal output from the frame memory 140 is input to the signal level adding circuit 94. The TV signal output from the video circuit 91 is input to the frame memory 150 at the timing of the second switching pulse for turning on the infrared LED 30. Then, the TV signal output from the frame memory 150 is inverted for each pixel by the signal level inverting circuit 93, and is input to the signal level adding circuit 94.

As described above, the signal level adding circuit 94 includes:
The TV signal from the signal level inverting circuit 93 and the TV signal from the frame memory 140 are input, and the signal levels of these TV signals are superimposed for each pixel. The TV signal superimposed by the signal level adding circuit 94 is provided to the video monitor 40, and the TV signal is displayed on the display window 11 as an image of the bill A.

Here, since the reflectance of the general ink in the visible wavelength range and the reflectance of the special ink in the infrared wavelength range are similar and relatively small, the video signal output from the frame memory 140 is The background portion of the bill A is white (because the background portion has a high reflectance), and the portion drawn with the general ink and the special ink is a video signal displayed in black. In addition, since the reflectance of the special ink in the infrared wavelength range is much larger than the reflectance of the general ink in the infrared wavelength range, the video signal output from the frame memory 150 includes the background portion of the bill A and the special signal. A video signal is displayed in which a portion drawn with ink is displayed in white and a portion drawn with general ink is displayed in black.

Subsequently, the TV signal output from the frame memory 150 is inverted by the signal level inverting circuit 93 for each pixel, so that the TV signal is drawn with the background portion of the bill A and the special ink. TV with black parts displayed in black and parts drawn with general ink in white
Signal.

Further, the signal level adding circuit 94
By superimposing the TV signal inverted by the signal level inverting circuit 93 and the TV signal output from the frame memory 140 for each pixel, the background portion of the bill A and the portion drawn with the general ink are white, The portion drawn with ink becomes a black TV signal, and an image drawn with special ink can be extracted. As a result, the portion printed with the special ink is displayed on the display window 11 as a black image.

Here, in the case where the banknote A is a genuine banknote printed with the special ink on the face and the general ink on the other part, the white and black of the pattern of the banknote A are reversed and the face of the face is reversed. A TV signal whose portion is painted black is output from the signal level inversion circuit 93 (see FIG. 4A). Further, a TV signal of the pattern of the bill A is output from the frame memory 140 (see FIG. 4B). Then, the signal levels of these TV signals are superimposed by the signal level adding circuit 94, whereby an image of only the face portion is displayed on the display window 11 (see FIG. 4C).

Therefore, when the authenticity of the bill A is determined based on the image displayed on the display window 11, since the face of the image of the genuine bill only emerges, the genuine bill can be easily determined. it can. Further, since the image of the counterfeit banknote created by color copying with the ink that reflects infrared rays is the same image as the whole when viewed with the naked eye, it is easy to determine the counterfeit banknote by color copying. Furthermore, since the image of a counterfeit banknote created by monochrome copying with a toner that absorbs infrared rays is entirely white, it is easy to determine a counterfeit banknote by monochrome copying. As described above, the authenticity of the bill A can be easily determined on the basis of the image displayed on the display window 11, so that a skilled operator is not required and there is no need to compare the bill with a sample.

(Fourth Embodiment) Subsequently, a fourth embodiment of the present invention will be described.
A paper sheet authenticity identification device according to the embodiment will be described. The fourth embodiment is different from the first embodiment shown in FIG. 1 in that an area sensor 80 having sensitivity in an infrared band and an imaging lens 81 are provided on the lower surface of a partition plate 50,
An area sensor 60 and an imaging lens 61 having sensitivity in the visible light band are provided on the side plate 10d, and the beam splitter 70 transmits infrared rays to go straight toward the area sensor 80 and reflects visible light. Side plate 10d
It is a dichroic mirror that goes straight toward. The details will be described below.

FIG. 9 is a sectional view showing a paper sheet authenticity discriminating apparatus 4 according to a fourth embodiment. As shown in FIG. 9, the paper sheet authenticity identification device 4 includes a rectangular parallelepiped light-shielding case 10, and a display window 11 is provided on an upper plate 10 a of the light-shielding case 10, and a reading window 12 is provided on a lower plate 10 b. I have. A protective glass is fitted in the display window 11 and the reading window 12. A green LED 20 that emits visible light is attached to one side plate 10c inside the light shielding case 10 obliquely downward. An infrared LED 3 for irradiating infrared rays is provided on the other side plate 10d inside the light shielding case 10.
0 is attached obliquely downward. For this reason,
The visible light emitted from the green LED 20 and the infrared LED
The entire surface of the reading window 12 is illuminated with the infrared light emitted from the light source 30.

A video monitor 40 such as a monochrome liquid crystal panel is provided below the display window 11 so that an image below the reading window 12 can be displayed. Further, the video monitor 40
A backlight unit 41 is provided below the light source and can illuminate the video monitor 40 with light so as to obtain a sufficient contrast. Here, a white fluorescent lamp is used as a light source of the backlight unit 41.

Below the backlight unit 41, a partition plate 50 suspended from the upper plate 10a is provided. On the lower surface of the partition plate 50, an area sensor 80 having sensitivity in the infrared band is provided. And the reading window 12 are opposed to each other. Further, below the area sensor 80, an image formed by the light reflected from the reading window 12 is displayed.
An imaging lens 81 that forms an image on the 0 sensor surface 80a is provided.

On the optical path between the area sensor 80 and the reading window 12, of the light reflected by the reading window 12, the infrared rays are transmitted and travel straight toward the area sensor 80, and the visible light is reflected. And a beam splitter 7 composed of a dichroic mirror for moving straight toward the side plate 10d.
0 is provided. Further, on the side plate 10d on the optical path of the light reflected by the beam splitter 70, an area sensor 60 having sensitivity in the visible light band and an image formed by the light reflected by the beam splitter 70 are formed on a sensor surface 60a of the area sensor 60. And an imaging lens 61 to be provided.

A circuit board 90 is provided on the upper surface of the partition plate 50. The circuit board 90 is provided with video circuits 91 and 92, a signal level inverting circuit 93 and a signal level adding circuit 94 shown in FIG. . The video circuit 91 is a circuit that receives a video signal output from the area sensor 60 and converts the video signal into a TV signal.
Is a circuit for receiving a video signal output from the area sensor 80 and converting the video signal into a TV signal. The signal level inversion circuit 93 is a circuit that inverts the signal level of the TV signal output from the video circuit 92.
Further, the signal level adding circuit 94 is a circuit that superimposes the signal level of the TV signal output from the signal level inverting circuit 93 and the TV signal output from the video circuit 91.

In the paper sheet authenticity discriminating apparatus 4, incident light is separated into visible light and infrared light by using a beam splitter 70 composed of a dichroic mirror, but a general beam splitter other than a dichroic mirror is used. Thus, incident light may be divided into two directions without wavelength separation. Also in this case, the area sensor 60 has sensitivity in the visible light band, and the area sensor 80 has sensitivity in the infrared band. An image is taken.

Next, the operation of the paper sheet authenticity discriminating apparatus 4 according to the fourth embodiment will be described. As shown in FIG. 11, when the paper sheet authenticity identification device 4 is placed on the bill A and the power switch (not shown) is turned on, the green LED shown in FIG.
20 and the infrared LED 30 are turned on, and the bill A is uniformly illuminated with the visible light emitted from the green LED 20 and the infrared light emitted from the infrared LED 30. The light reflected by the bill A travels straight upward and enters the beam splitter 70. Of the light incident on the beam splitter 70, the infrared ray passes through the beam splitter 70 and forms an imaging lens 81.
Forms an image on the sensor surface 80a of the area sensor 80.
Also, of the light incident on the beam splitter 70, visible light is reflected by the beam splitter 70,
1 forms an image on the sensor surface 60a of the area sensor 60.

When an image is formed on the sensor surface 80a of the area sensor 80, a video signal of this image is output from the area sensor 80. The video signal output from the area sensor 80 is converted into a TV signal by the video circuit 92 and input to the signal level inversion circuit 93. The signal level of the input TV signal is inverted for each pixel by a signal level inverting circuit 93 and input to a signal level adding circuit 94. When an image is formed on the sensor surface 60 a of the area sensor 60, a video signal of this image is output from the area sensor 60. The video signal output from the area sensor 60 is converted into a TV signal by the video circuit 91 and input to the signal level adding circuit 94.

As described above, the signal level adding circuit 94 includes:
TV signal from signal level inverting circuit 93 and video circuit 91
, And the signal levels of these TV signals are superimposed for each pixel. The TV signal superimposed by the signal level adding circuit 94 is output to the video monitor 4
0, and the TV signal is displayed on the display window 11 as an image of the bill A.

Here, since the reflectance of the general ink in the visible wavelength range and the reflectance of the special ink in the infrared wavelength range are similar and relatively small, the video signal output from the area sensor 60 is The background portion of the bill A is white (because the background portion has a high reflectance), and the portion drawn with the general ink and the special ink is a video signal displayed in black. Further, since the reflectance of the special ink in the infrared wavelength range is much larger than that of the general ink in the infrared wavelength range, the area sensor 8
The video signal output from 0 is a video signal in which the background portion of the bill A and the portion drawn with the special ink are white, and the portion drawn with the general ink is displayed in black.

Subsequently, the signal level inversion circuit 93 inverts the monochrome level of the TV signal output from the video circuit 92 for each pixel, so that the TV signal becomes
The background signal and the portion drawn with the special ink are black, and the portion drawn with the general ink is a white TV signal.

Further, the signal level adding circuit 94
By superimposing the TV signal inverted by the signal level inverting circuit 93 and the TV signal output from the video circuit 91 for each pixel, the background portion of the bill A and the portion drawn with the general ink are white, The portion drawn with ink becomes a black TV signal, and an image drawn with special ink can be extracted. As a result, the portion printed with the special ink is displayed on the display window 11 as a black image.

Here, in the case where the banknote A is a genuine banknote printed with special ink on the face and general ink on the other part, the white and black of the pattern of the banknote A are inverted and the face of the face is inverted. A TV signal whose portion is painted black is output from the signal level inversion circuit 93 (see FIG. 4A). In addition, a TV signal of the pattern of the bill A is output from the video circuit 91 (see FIG. 4B). Then, these TV signals are superimposed by the signal level adding circuit 94, whereby an image of only the face portion is displayed on the display window 11 (FIG. 4).
(C)).

Accordingly, when the authenticity of the bill A is determined based on the image displayed on the display window 11, only the face of the image of the genuine bill emerges, so that the genuine bill can be easily determined. it can. Further, since the image of the counterfeit banknote created by color copying with the ink that reflects infrared rays is entirely black, it is easy to determine the counterfeit banknote by color copying. Further, since the image of the counterfeit banknote created by monochrome copying using the toner that absorbs infrared rays also becomes black, it is easy to determine the counterfeit banknote by monochrome copying. As described above, whether the bill A is true or false is determined by the display window 1.
Since it can be easily performed based on the image displayed in 1, there is no need for a skilled operator, and there is no need to compare it with a sample.

The reason why the amount of light received by the area sensors 60 and 80 due to the light reflected by the general ink portion is substantially the same is that the irradiation amounts of visible light and infrared light are substantially equal and the light reception of the area sensors 60 and 80 is almost equal. This is because the sensitivities are the same. Here, when the irradiation amounts of visible light and infrared light are different, by using the area sensors 60 and 80 having different light receiving sensitivities, the light receiving amounts of the area sensors 60 and 80 can be made substantially equal. Also, the area sensor 6
Even when the light receiving sensitivities of 0 and 80 are different, the area sensor 60,
80 can be made substantially equal to the amount of received light.

(Fifth Embodiment) Next, a paper sheet authenticity discriminating apparatus 5 according to a fifth embodiment will be described. FIG. 12 is a cross-sectional view showing the paper sheet authenticity identification device 5. FIG.
3 is a block diagram showing an internal configuration of the paper sheet authenticity identification device 5. FIG. This fifth embodiment differs from the second embodiment shown in FIG. 5 in that an area sensor 80 and an imaging lens 81 having sensitivity in the infrared band are provided on the lower surface of the partition plate 50, and the side plate 10d In addition, an area sensor 60 and an imaging lens 61 having sensitivity in a visible light band are provided, and a beam splitter 70 transmits infrared rays to travel straight toward the area sensor 80, and reflects visible light to form a side plate. 1
This is a dichroic mirror that moves straight toward 0d. Other configurations are the same as or equivalent to the second embodiment. Note that the same or equivalent components as those of the second embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIGS. 12 and 13, a light source 100 having both visible light and infrared light is attached to one side plate 10c inside the light shielding case 10 obliquely downward. Bill A by the light emitted
Are illuminated uniformly. The light reflected by the bill A travels straight upward and is separated into visible light and infrared light by the beam splitter 70. The visible light enters the area sensor 60 and the infrared light enters the area sensor 80, and the area sensors 60 and 80 output video signals. The video signal output from the area sensor 80
The signal is converted to a V signal and input to the signal level inversion circuit 93. The signal level of the input TV signal is inverted for each pixel by a signal level inverting circuit 93 and input to a signal level adding circuit 94. When an image is formed on the sensor surface 60 a of the area sensor 60, a video signal of this image is output from the area sensor 60. The video signal output from the area sensor 60 is converted into a TV signal by the video circuit 91 and input to the signal level adding circuit 94.

As described above, the signal level adding circuit 94 includes:
TV signal from signal level inverting circuit 93 and video circuit 91
, And the signal levels of these TV signals are superimposed for each pixel. The TV signal superimposed by the signal level adding circuit 94 is output to the video monitor 4
0, and the TV signal is displayed on the display window 11 as an image of the bill A.

As described above, when the banknote A is a counterfeit banknote, an image in which the entire surface is black is displayed on the display window 11 and the banknote A is displayed.
Is a genuine banknote, the image of only the face is displayed on the display window 1.
1 is displayed. Therefore, when the authenticity of the banknote A is determined based on the image displayed on the display window 11, since only the face portion of the image of the authentic banknote emerges, the authentic banknote can be easily determined. Further, since the image of the counterfeit banknote created by color copying with the ink that reflects infrared rays is entirely black, it is easy to determine the counterfeit banknote by color copying. Further, since the image of the counterfeit banknote created by monochrome copying using the toner that absorbs infrared rays also becomes black, it is easy to determine the counterfeit banknote by monochrome copying. As described above, the authenticity of the bill A can be easily determined on the basis of the image displayed on the display window 11, so that a skilled operator is not required and there is no need to compare the bill with a sample.

The present invention is not limited to the above embodiment, but can be modified as follows, for example, without departing from the spirit of the present invention.

(1) In the above embodiment, bills are used as bills. However, in addition to bills, stamps, securities, and other bills can be identified.

(2) In the above embodiment, an infrared ray is used as the light beam of the second wavelength, but an ultraviolet ray may be used.

(3) In the first, second, fourth, and fifth embodiments, the light reflected by the bill A is split into the area sensor 60 and the area sensor 80 by using the beam splitter 70. Without using 70, the partition plate 5
0, the area sensor 60 and the area sensor 80 are arranged side by side, and the light reflected by the bill A is reflected by the area sensor 60.
And the area sensor 80 may be made to be able to enter simultaneously.

[0080]

The paper sheet authenticity discriminating apparatus according to the present invention is configured as described above, so that the following effects can be obtained.

That is, the counterfeit banknote becomes an image similar to that seen by the naked eye or a white level image, and the genuine banknote becomes an image in which a specific pattern emerges. Judgment becomes easy. Therefore, the authenticity of the paper sheet can be easily determined without the need for a skilled operator and without comparing with a sample.

Further, the light of the first wavelength and the second
Just by irradiating the light of the wavelength, an image in which a different part between the image of the light of the first wavelength and the image of the light of the second wavelength emerges is displayed on the display means. In this way, anyone can use the paper sheet authenticity identification device with a simple operation, and it is possible to easily determine the authenticity from the display on the display means.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a paper sheet authenticity identification apparatus.

FIG. 2 is a block diagram showing an internal configuration of the paper sheet authenticity identification apparatus of FIG. 1;

FIG. 3 is a schematic diagram illustrating a use state of the paper sheet authenticity identification device of FIG. 1;

FIG. 4A is a diagram illustrating an image output from a signal level inversion circuit. (B) is a diagram showing an image output from the area sensor. (C) is a figure which shows the image displayed on the video monitor.

FIG. 5 is a cross-sectional view illustrating a second embodiment of a paper sheet authenticity identification apparatus.

FIG. 6 is a block diagram showing an internal configuration of the paper sheet authenticity identification device of FIG. 5;

FIG. 7 is a cross-sectional view showing a third embodiment of a paper sheet authenticity identification apparatus.

8 is a block diagram illustrating an internal configuration of the paper sheet authenticity identification device in FIG. 7;

FIG. 9 is a cross-sectional view illustrating a fourth embodiment of a paper sheet authenticity identification apparatus.

FIG. 10 is a block diagram showing an internal configuration of the paper sheet authenticity identification device of FIG. 9;

FIG. 11 is a schematic diagram illustrating a use state of the paper sheet authenticity identification device of FIG. 9;

FIG. 12 is a cross-sectional view illustrating a fifth embodiment of a paper sheet authenticity identification apparatus.

13 is a block diagram illustrating an internal configuration of the paper sheet authenticity identification device in FIG.

[Explanation of symbols]

1, 2, 3, 4, 5 ... paper sheet authenticity identification device, 20 ... green LED, 30 ... infrared LED, 40 ... video monitor, 60
... area sensor, 61 ... imaging lens, 70 ... beam splitter, 80 ... area sensor, 81 ... imaging lens, 93
... Signal level inverting circuit, 94 ... Signal level adding circuit, 1
00: light source, 110: area sensor, 120: illumination switching circuit, 130: video switching circuit, A: bill.

Claims (6)

[Claims] 1. A general ink in which the reflectance for a first wavelength and the reflectance for a second wavelength different from the first wavelength are close to each other, and the reflectance for the first wavelength is similar to that of the general ink. For the second wavelength, genuine paper sheets printed with a special ink having a reflectance different from that of the general ink, and a counterfeit printed on one of the general ink and the special ink. A paper sheet authenticity discriminating apparatus for distinguishing between a paper sheet and a paper sheet, a first illuminating means for illuminating the paper sheet with the first wavelength light, and illuminating the paper sheet with the second wavelength light A second illuminating unit, a first area sensor having sensitivity to the first wavelength, and a first imaging unit that forms an image of light reflected by the paper sheet on the first area sensor. A first imaging unit including an image optical system, and imaging the paper sheet; A second area sensor having sensitivity to the second wavelength, and a second imaging optical system that forms an image of light reflected by the sheet on the second area sensor; A second image pickup unit for picking up an image of a paper sheet; and image data for the first wavelength obtained by the first area sensor and image data for the second wavelength obtained by the second area sensor. A paper sheet authenticity identification apparatus comprising: an image extracting unit that extracts an image drawn with the special ink based on the image data; and a display unit that displays the image extracted by the image extracting unit. 2. A general ink in which a reflectance for a first wavelength and a reflectance for a second wavelength different from the first wavelength are similar to each other, and a reflectance for the first wavelength is similar to that of the general ink. For the second wavelength, genuine paper sheets printed with a special ink having a reflectance different from that of the general ink, and a counterfeit printed on one of the general ink and the special ink. A sheet authenticity discriminating apparatus for identifying a sheet; an illuminating means for illuminating the sheet with light in a wavelength band including a range of the first wavelength and the second wavelength; A first area sensor having sensitivity to a wavelength, and a first imaging optical system that forms an image of light reflected by the sheet on the first area sensor; A first imaging unit for imaging the image, and a sensitivity to the second wavelength. And a second imaging optical system that forms an image of the light reflected by the sheet on the second area sensor, and a second area sensor that captures the sheet. Imaging means, and image data with the special ink, based on image data for the first wavelength obtained by the first area sensor and image data for the second wavelength obtained by the second area sensor A paper sheet authenticity discriminating apparatus comprising: an image extracting unit that extracts a selected image; and a display unit that displays the image extracted by the image extracting unit. 3. The image forming apparatus according to claim 1, further comprising: a light branching unit that branches light reflected by the paper sheet in two directions of the first imaging optical system and the second imaging optical system. Claim 1
Or the paper sheet authenticity identification device according to 2. 4. A general ink in which the reflectance for the first wavelength and the reflectance for a second wavelength different from the first wavelength are similar to each other, and the reflectance for the first wavelength is similar to that of the general ink. For the second wavelength, genuine paper sheets printed with a special ink having a reflectance different from that of the general ink, and a counterfeit printed on one of the general ink and the special ink. A paper sheet authenticity discriminating apparatus for distinguishing between a paper sheet and a paper sheet, a first illuminating means for illuminating the paper sheet with the first wavelength light, and illuminating the paper sheet with the second wavelength light A second illuminating means, an area sensor having sensitivity to the first wavelength and the second wavelength, and an image forming optical system for forming an image of light reflected by the paper sheet on the area sensor. Imaging means for imaging the paper sheet; First and second frame memories for storing image data obtained by the sensor; illumination switching means for alternately switching illumination by the first illumination means and illumination by the second illumination means; Image data for the first wavelength obtained by the area sensor under illumination by the illumination means is stored in the first frame memory, and obtained by the area sensor under illumination by the second illumination means. Switching means for switching a frame memory in which each of the image data is stored in conjunction with a switching timing of the illumination switching means so that image data for the second wavelength is stored in the second frame memory; Image data for the first wavelength stored in one frame memory and the image data stored in the second frame memory. An image extracting unit that extracts an image drawn with the special ink based on image data for a second wavelength, and a display unit that displays the image extracted by the image extracting unit. Paper sheet authenticity identification device. 5. The special ink has a higher reflectance for the second wavelength than the reflectance for the first wavelength, and the image extracting means sets a black-and-white level of image data for the second wavelength to Image data inverting means for inverting for each pixel; superimposed image data in which image data for the first wavelength and image data for the second wavelength output from the image data inverting means are superimposed for each pixel; 5. The image forming apparatus according to claim 1, further comprising: a superimposing unit configured to generate an image drawn with the special ink based on the superimposed image data generated by the superimposing unit. 6. Paper sheet authenticity identification device. 6. The paper sheet according to claim 1, wherein the light of the first wavelength and the light of the second wavelength are a combination of visible light and infrared light. Authenticator.