JP4163822B2 - Fluorescence detection device for paper sheets - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fluorescence detection apparatus used for inspecting whether or not a paper sheet being conveyed contains a fluorescence component.
[0002]
[Prior art]
Conventionally, there is JP-T 9-507326 as a technique in such a field. The apparatus described in this publication irradiates the banknotes with ultraviolet light, measures the level of ultraviolet light reflected by the banknotes using the first photocell, and at the same time, determines the amount of fluorescence generated on the banknotes by the second level. It measures with a photocell, compares each measured quantity with a reference level, and discriminates the authenticity of a banknote.
[0003]
[Problems to be solved by the invention]
However, the conventional apparatus described above has the following problems. That is, the amount of ultraviolet rays irradiated to the banknote may become unstable at the beginning of lighting of the light source, and may vary with voltage fluctuations or deterioration over time. The banknote may not be accurately inspected. In addition, there exist Unexamined-Japanese-Patent No. 10-3561, Unexamined-Japanese-Patent No. 10-40436, and Unexamined-Japanese-Patent No. 10-208105 etc. as what distinguishes the authenticity of a banknote using an ultraviolet-ray.
[0004]
The present invention has been made to solve the above-described problems. In particular, fluorescence detection for paper sheets that enables accurate paper sheet inspection by ultraviolet irradiation and at the same time promotes downsizing. An object is to provide an apparatus.
[0005]
[Means for Solving the Problems]
The fluorescence detection apparatus for paper sheets of the present invention according to claim 1 is for paper sheets that detects the fluorescence emitted from the paper sheets by irradiating the paper sheets with ultraviolet rays while the paper sheets are being conveyed. A fluorescent detection device, and an ultraviolet LED that is accommodated in the housing and irradiates light toward the transport path of the paper sheet, and is accommodated in the housing and disposed between the ultraviolet LED and the transport path, An ultraviolet transmission filter that transmits the ultraviolet component of the irradiation light, and an ultraviolet monitor that is contained in the housing and detects the ultraviolet component that is reflected by the ultraviolet transmission filter and returned from the irradiation light emitted from the ultraviolet LED. The light quantity of ultraviolet LED is controlled based on the output signal from an ultraviolet monitor.
[0006]
This fluorescence detection apparatus is an apparatus for detecting whether or not the paper sheet contains a fluorescent component in the middle of the transport path and using it for subsequent paper sheet processing. In this apparatus, the paper sheet is irradiated with light emitted from the ultraviolet LED in the housing. At this time, the irradiation light is applied to the paper sheet after passing through the ultraviolet transmission filter, and Paper sheets are illuminated by the ultraviolet component. In addition, there is a possibility that accurate paper sheet inspection cannot be performed unless the amount of ultraviolet light applied to the paper sheet is always managed in a constant state. Therefore, as one means of management, not the ultraviolet light transmitted through the ultraviolet transmission filter but the ultraviolet light reflected by the ultraviolet transmission filter is detected by the ultraviolet monitor, and the light quantity of the ultraviolet LED is determined based on the output signal from the ultraviolet monitor. To manage over time. As described above, by utilizing the reflected ultraviolet light, the ultraviolet monitor can be accommodated in the same housing as the ultraviolet LED, and the apparatus can be made compact and easily incorporated into the paper sheet inspection apparatus. It will be.
[0011]
The fluorescence detection apparatus for paper sheets of the present invention according to claim 2 is for paper sheets that detects the fluorescence emitted from the paper sheets by irradiating the paper sheets with ultraviolet rays while the paper sheets are being conveyed. A fluorescent detection device, and an ultraviolet LED that is accommodated in the housing and irradiates light toward the transport path of the paper sheet, and is accommodated in the housing and disposed between the ultraviolet LED and the transport path, A beam splitter that separates the irradiated light into a visible component and an ultraviolet component, reflects the visible component, and transmits the ultraviolet component, and a visible light that is received in the housing and is reflected by the beam splitter and returns. And a monitor for controlling the light quantity of the ultraviolet LED based on an output signal from the visible light monitor.
[0012]
This fluorescence detection apparatus is an apparatus for detecting whether or not the paper sheet contains a fluorescent component in the middle of the transport path and using it for subsequent paper sheet processing. In this apparatus, the paper sheet is irradiated with light emitted from the ultraviolet LED in the housing. At this time, the irradiation light includes a visible component and an ultraviolet component, and an ultraviolet component that has passed through the beam splitter is included. The paper sheet is illuminated by being applied to the paper sheet. In addition, there is a possibility that accurate paper sheet inspection cannot be performed unless the amount of ultraviolet light applied to the paper sheet is always managed in a constant state. Therefore, as one means of management, not the ultraviolet component transmitted through the beam splitter but the visible component reflected by the beam splitter is detected by a visible light monitor, and an ultraviolet LED is detected based on an output signal from the visible light monitor. The amount of light is managed over time. In this way, by using the reflected ultraviolet light, it becomes possible to accommodate the visible light monitor in the same housing as the ultraviolet LED, and the device can be made compact and easy to incorporate into a paper sheet inspection apparatus. Will do.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of a fluorescence detection device for paper sheets according to the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 is a cross-sectional view showing a main part of a paper sheet inspection apparatus to which a fluorescence detection device for paper sheets is applied. What is to be inspected by the paper sheet inspection apparatus 1 is the authenticity determination of a bill that is an example of a paper sheet. Specifically, the determination is made between a color copied counterfeit bill and a regular bill. It is. This color copy sheet contains a large amount of fluorescent components, and authenticity determination is performed by paying attention to this point.
[0015]
The paper sheet inspection apparatus 1 is provided with a linear transport path 4 formed so as to be sandwiched between upper and lower guide plates 2 and 3. In the middle of the transport path 4, transport rollers 5 and 6 are provided. It arrange | positions and the banknote 7 is reliably conveyed toward the discharge side by each conveyance roller 5 and 6. FIG. A bill recognizing device 8 for identifying a denomination is arranged in the middle of the transport path 4.
[0016]
Although not shown, the inside of the bill (paper sheet) recognition device 8 has a structure in which the surface of the bill 7 is illuminated by a light source such as an LED and the reflected light from the bill 7 is captured by a CCD camera. And the image imaged with this camera and the known image data are collated, and the denomination of a bill is discriminated. However, in recent years, due to the high accuracy of color copying, it is difficult to determine the authenticity of the banknote 7 by image recognition alone.
[0017]
Therefore, the fluorescence detection device 10 is arranged on the upstream side of the banknote recognition device 8. As shown in FIG. 2, in the fluorescence detection device 10, an ultraviolet LED 12 that irradiates light toward the conveyance path 4 of the banknote 7 is accommodated in the housing 11, and the ultraviolet LED 12 is fixed to the housing 11. The LED 12 used here is an ultraviolet lamp containing a visible light component. The reason why the LED 12 is used as the light source is that even if the housing 11 is small, the housing space may be small, the luminance variation is small, and the light fluctuation with time is small. It is optimal for the detection device 10.
[0018]
A window portion 13 for extracting light to the outside is provided on the lower surface of the casing 11, and a dust-proof glass plate 14 is fitted into the window portion 13 with an adhesive or the like. The dust-proof glass plate 14 has an ultraviolet transmittance. Quartz glass is very high. An ultraviolet transmission filter 15 is attached to the upper surface (inner surface) of the dust-proof glass plate 14, and the ultraviolet filter 15 is located on the optical axis G of the ultraviolet LED 12. The dust-proof glass plate 14 may be ordinary so-called white plate glass.
[0019]
Accordingly, the ultraviolet transmissive filter 15 is accommodated in the housing 11, and the light emitted from the ultraviolet LED 12 passes through the ultraviolet transmissive filter 15, so that the ultraviolet component (for example, about 300 to 400 nm) is a dust-proof glass plate. 14 to the transport path 4. And the banknote 7 sent to the right under the dust-proof glass plate 14 through the conveyance path | route 4 is illuminated with an ultraviolet-ray.
[0020]
A light receiving element (photosensor) 16 for detecting fluorescence emitted from the surface of the banknote 7 is accommodated in the space S formed by the light shielding wall P of the housing 11. Therefore, when the banknote 7 illuminated by ultraviolet rays contains a fluorescent component, the excited fluorescence is emitted from the banknote 7 and can be detected by the sensor 16. This is equivalent to the case where the color-copyed counterfeit banknote 7 is sent into the conveyance path 4, and the color copy paper contains a large amount of fluorescent components. On the other hand, the regular banknote contains almost no fluorescent component, and the voltage change of the sensor 16 is extremely small.
[0021]
In the space S, an ultraviolet cut filter 17 is attached to the upper surface (inner surface) of the dust-proof glass plate 14. The reason for adopting such an ultraviolet cut filter 17 is that an ultraviolet component reflected from the banknote 7 is included, and this ultraviolet component has a high energy characteristic. It is because it is necessary to remove a component.
[0022]
Here, unless the amount of ultraviolet irradiation light applied to the banknote 7 is always managed in a constant state, an accurate paper sheet inspection cannot be performed. Therefore, as one means of management, not the ultraviolet rays transmitted through the ultraviolet transmission filter 15 but the ultraviolet rays reflected by the ultraviolet transmission filter 15 are used.
[0023]
That is, the housing 11 houses an ultraviolet monitor 18 made of a photosensor. The ultraviolet monitor 18 is disposed on the ultraviolet LED 12 side, can receive reflected ultraviolet light, and manages the light amount of the ultraviolet LED 12 over time based on an output signal from the ultraviolet monitor 18. In this way, by utilizing the reflected ultraviolet light, the ultraviolet monitor 18 can be accommodated in the same housing 11 as the ultraviolet LED 12, and the apparatus 10 can be made compact and easily incorporated into the paper sheet inspection apparatus 1. Can be improved.
[0024]
Next, as shown in FIG. 3, as the related art, without employing an ultraviolet transmitting filter 15, are those aimed ultra thin fluorescence detection device 20. In the device 20, an ultraviolet LED 22 that irradiates light toward the conveyance path 4 of the banknote 7 is accommodated in a housing 21, and the ultraviolet LED 22 is fixed to the housing 21. The LED 22 used here is a lamp that hardly contains a visible light component, and is an ultraviolet lamp that does not need to consider removal of the visible component by a filter.
[0025]
A window portion 23 for extracting light to the outside is provided on the lower surface of the housing 21, and a dustproof glass plate 24 is fitted into the window portion 23 with an adhesive or the like, and the dustproof glass plate 24 has an ultraviolet transmittance. Quartz glass is very high. Therefore, the ultraviolet component (for example, about 200 to 400 nm) emitted from the ultraviolet LED 22 is emitted to the transport path 4 through the dust-proof glass plate 24. And the banknote 7 sent to the right under the dust-proof glass plate 24 through the conveyance path | route 4 is illuminated with an ultraviolet-ray.
[0026]
A light receiving element (photosensor) 26 for detecting the fluorescence emitted from the surface of the banknote 7 is accommodated in the space S formed by the light shielding wall P of the housing 21. Therefore, when the banknote 7 illuminated by the ultraviolet rays contains a fluorescent component, the excited fluorescence is emitted from the banknote 7 and is detected by the sensor 26. Thereby, the authenticity of the banknote 7 is discriminated. In addition, the ultraviolet cut filter 27 is affixed on the upper surface (inner surface) of the dust-proof glass plate 24, and the reason for employing this is as described above.
[0027]
Here, unless the amount of ultraviolet irradiation light applied to the banknote 7 is always managed in a constant state, an accurate paper sheet inspection cannot be performed. Therefore, as one means of management, not the ultraviolet light transmitted through the dust-proof glass plate 24 but the ultraviolet light reflected by the dust-proof glass plate 24 is used.
[0028]
That is, the housing 21 accommodates an ultraviolet monitor 28 composed of a photosensor. The ultraviolet monitor 28 is disposed on the ultraviolet LED 22 side, can receive reflected ultraviolet light, and manages the light quantity of the ultraviolet LED 22 over time based on an output signal from the ultraviolet monitor 28. As described above, the advantage of using the reflected ultraviolet light is as described above.
[0029]
Next, as illustrated in FIG. 4, in the fluorescence detection device 30 according to the related art, an ultraviolet LED 32 that irradiates light toward the conveyance path 4 of the banknote 7 is accommodated in a housing 31, and the ultraviolet LED 32 is a housing 31. It is fixed to. The LED 32 used here is an ultraviolet lamp containing a visible light component. The reason why the LED 32 is used as the light source is as described above.
[0030]
A window 33 for extracting light to the outside is provided on the lower surface of the housing 31, and a dustproof glass plate 34 is fitted into the window 33 with an adhesive or the like, and the dustproof glass plate 34 has an ultraviolet transmittance. Quartz glass is very high. An ultraviolet transmission filter 35 is attached to the upper surface (inner surface) of the dust-proof glass plate 34, and the ultraviolet filter 35 is located on the optical axis G of the ultraviolet LED 32.
[0031]
A light receiving element (photosensor) 36 for detecting the fluorescence emitted from the surface of the banknote 7 is accommodated in the space S formed by the light shielding wall P of the housing 31. Therefore, when the banknote 7 illuminated by the ultraviolet rays contains a fluorescent component, the excited fluorescence is emitted from the banknote 7 and can be detected by the sensor 36. Thereby, the authenticity of the banknote 7 is discriminated. An ultraviolet cut filter 37 is attached to the upper surface (inner surface) of the dust-proof glass plate 34. The reason why such an ultraviolet cut filter 37 is employed is as described above.
[0032]
Here, unless the amount of ultraviolet irradiation light applied to the banknote 7 is always managed in a constant state, an accurate paper sheet inspection cannot be performed. Therefore, a half mirror 39 is attached to the upper surface of the ultraviolet transmission filter 35, and ultraviolet rays reflected by the half mirror 39 are used instead of the ultraviolet rays reflected by the ultraviolet transmission filter 35.
[0033]
That is, the housing 31 accommodates an ultraviolet monitor 38 made of a photosensor. The ultraviolet monitor 38 is arranged on the ultraviolet LED 32 side and can receive reflected light with high luminance obtained by the reflection of the half mirror 39. Therefore, since the light quantity of the ultraviolet LED 32 is managed over time based on the output signal from the ultraviolet monitor 38, the luminance change of the ultraviolet LED 32 can be managed at a high level, and the sensitivity of the ultraviolet monitor 38 needs to be increased. Instead, an inexpensive ultraviolet monitor 38 can be used.
[0034]
The fluorescence detection apparatus of the present invention is not limited to the embodiment described above. For example, in the embodiment shown in FIG. 2, a beam splitter 15 </ b> A that reflects the visible component and transmits the ultraviolet component is used instead of the ultraviolet transmission filter 15, and visible light that is an example of a photosensor is used instead of the ultraviolet monitor 18. A monitor 18A is employed. Other components are common.
[0035]
In this case, the banknote 7 is irradiated with light emitted from the ultraviolet LED 12 in the housing. The irradiation light at this time includes a visible component and an ultraviolet component, and the ultraviolet component that has passed through the beam splitter 15A is paper. Paper leaves are illuminated by the leaves. In addition, the amount of ultraviolet light applied to the banknote 7 cannot be accurately inspected unless it is always managed in a constant state.
[0036]
Therefore, as one means of management, not the ultraviolet component transmitted through the beam splitter 15A but the visible component reflected by the beam splitter 15A is detected by the visible light monitor 18A, and the output signal from the visible light monitor 18A is detected. Based on this, the light quantity of the ultraviolet LED 12 is managed over time.
[0037]
The paper sheets applied to the present invention are not limited to banknotes, and can be applied to, for example, cash vouchers, securities, and bills.
[0038]
【The invention's effect】
Since the fluorescence detection apparatus for paper sheets according to the present invention is configured as described above, the following effects are obtained. That is, a fluorescence detection apparatus for paper sheets that detects the fluorescence emitted from the paper sheets by irradiating the paper sheets with ultraviolet rays while the paper sheets are being transported, and is housed in a housing and An ultraviolet LED that irradiates light toward the leaf conveyance path, an ultraviolet transmission filter that is accommodated in the housing and is disposed between the ultraviolet LED and the conveyance path, and transmits an ultraviolet component of the irradiation light, and the housing An ultraviolet monitor that detects the ultraviolet component that is reflected by the ultraviolet transmission filter and returned from the irradiation light emitted from the ultraviolet LED, and is based on the output signal from the ultraviolet monitor. By controlling the amount of light, it is possible to perform accurate paper sheet inspection by ultraviolet irradiation, and at the same time, it is possible to promote downsizing of the apparatus itself.
[0041]
Similarly, the fluorescence detection apparatus according to the present invention is housed in a housing, and is arranged between the ultraviolet LED and the transport path to separate the irradiation light into a visible component and an ultraviolet component, and reflect the visible component to reflect the ultraviolet component. A visible beam component that is reflected by the beam splitter and returned by the beam splitter is detected by the visible light monitor, enabling accurate paper sheet inspection by UV irradiation, and at the same time making the device compact. Can be promoted.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a main part of a paper sheet inspection apparatus to which a fluorescence detection apparatus according to the present invention is applied.
FIG. 2 is a cross-sectional view showing a first embodiment of a fluorescence detection apparatus according to the present invention.
3 is a cross-sectional view illustrating a fluorescence detection equipment according to the related art.
4 is a sectional view showing a fluorescence detection equipment according to the related art.

Claims (2)

A fluorescence detection device for paper sheets that detects the fluorescence emitted from the paper sheets by irradiating the paper sheets with ultraviolet rays while transporting the paper sheets,
An ultraviolet LED that is housed in a housing and emits light toward the transport path of the paper sheet;
An ultraviolet transmissive filter that is housed in the housing and disposed between the ultraviolet LED and the transport path, and transmits an ultraviolet component of the irradiation light;
Among the irradiation light emitted from the ultraviolet LED housed in the housing, an ultraviolet monitor that detects an ultraviolet component reflected and returned by the ultraviolet transmission filter, and
A fluorescence detection apparatus for paper sheets, wherein the light quantity of the ultraviolet LED is controlled based on an output signal from the ultraviolet monitor. A fluorescence detection device for paper sheets that detects the fluorescence emitted from the paper sheets by irradiating the paper sheets with ultraviolet rays while transporting the paper sheets,
An ultraviolet LED that is housed in a housing and emits light toward the transport path of the paper sheet;
A beam splitter housed in the housing and disposed between the ultraviolet LED and the transport path to separate the irradiation light into a visible component and an ultraviolet component, reflect the visible component and transmit the ultraviolet component; ,
A visible light monitor that is housed in the housing and detects the visible component reflected back by the beam splitter;
A fluorescence detection apparatus for paper sheets, wherein the light quantity of the ultraviolet LED is controlled based on an output signal from the visible light monitor.

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