JP2003296792A - Fluorescence detecting sensor for paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluorescence detecting sensor for paper which receives fluorescence generated from sheets of paper with precision, and is not affected by the state of the paper. <P>SOLUTION: A light transmission/reflection mirror 30 is used for the paper fluorescence detecting sensor 10, in order to simultaneously satisfy emitting an UV-ray in a direction orthogonally crossed with a carrier route 4 and also properly receiving fluorescence from the paper 7. The mirror receives a light emitted from an UV source and passing through an UV-ray transmission filter 15, and generates a light having a light axis R2 which is orthogonally crossed with the paper carrier route. Fluorescence emitted from the paper which is irradiated with the light reaches an UV cut filter 17 via the mirror 30, and the light passing through the UV cut filter is received by a light receiving element 16. The inexpensive light transmission/reflection mirror such as a half mirror is utilized for the sensor 10, so that the sensor itself is made to be inexpensive, and a production cost is reduced. Besides, a degree of freedom is increased in arranging respective configuration parts inside a casing 11 by utilizing the light transmission/reflection mirror for the paper fluorescence detecting sensor. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper sheet fluorescence detection sensor for use in determining the type and authenticity of paper sheets such as banknotes.

[0002]

2. Description of the Related Art Conventionally, as a technique in such a field, there is Japanese Patent Publication No. 9-507326. The device described in this publication irradiates a bill with ultraviolet rays and measures the level of ultraviolet light reflected by the bill using a first photocell, and at the same time, measures the amount of fluorescence generated in the bill by a second amount. Measure with a photocell, compare each measured amount with a reference level,
This is to distinguish the authenticity of bills.

[0003]

However, the conventional device described above has the following problems. That is, when the bills are irradiated with ultraviolet rays obliquely from above, it is possible to receive light relatively appropriately for flaps of the bills on the transport path, but the bills are wrinkled or folded. In this state, the required range of the bill will not be sufficiently irradiated with ultraviolet light. In this case, the generated fluorescence becomes uneven, and as a result, the received light output of the fluorescence tends to become uneven, and it is difficult to accurately receive the fluorescence.

The present invention has been made in order to solve the above-mentioned problems, and in particular, the fluorescence of paper sheets is made to accurately receive the fluorescence emitted from the paper sheets, and the fluorescence of the paper sheets is not easily influenced by the state of the paper sheets. An object is to provide a detection sensor.

[0005]

A paper sheet fluorescence detection sensor according to the present invention detects a fluorescence emitted from a paper sheet by irradiating the paper sheet with light while the paper sheet is being conveyed. In the fluorescence detection sensor, the ultraviolet light source housed in the housing, the ultraviolet light transmission filter placed in front of the ultraviolet light source while being housed in the housing, and the ultraviolet light transmission filter housed in the housing and passed through the ultraviolet light transmission filter A light transmissive / reflective mirror that transmits and reflects light, and applies light that is orthogonal to the paper sheet conveyance path, and is housed in a housing,
It is provided with a light receiving element that receives fluorescence emitted from paper sheets by irradiation of ultraviolet rays through a light transmission / reflection type mirror, and an ultraviolet ray cut filter arranged between the light receiving element and the light transmission / reflection type mirror. Characterize.

In this paper sheet fluorescence detection sensor, the paper sheet is irradiated with ultraviolet rays, and the fluorescence emitted from the paper sheet is received by the light receiving element to determine the type and authenticity of the paper sheet. This is an invention that is premised on doing. In addition, the paper sheets on the conveyance path are not always conveyed in a constant state, and may be flapping on the conveyance path, or the paper sheets themselves may be wrinkled or folded. is there. In any of these situations, it is necessary to make it difficult to cause unevenness in the output from the light receiving element. Therefore, in the present invention, applying ultraviolet light in a direction orthogonal to the transport path,
A light transmissive / reflective mirror is used to simultaneously satisfy the requirement of appropriately receiving the fluorescence from the paper sheets. This light transmission / reflection type mirror receives the light emitted from the ultraviolet light source and passed through the ultraviolet transmission filter, and produces light having an optical axis orthogonal to the paper sheet conveyance path.
And, the fluorescence emitted from the paper sheets illuminated by this light is
The light reaching the ultraviolet cut filter via the light transmission / reflection type mirror and passing through the ultraviolet cut filter is received by the light receiving element. Since such a paper sheet fluorescence detection sensor uses an inexpensive light transmission / reflection type mirror such as a half mirror, the sensor itself is made inexpensive and the manufacturing cost is reduced. Moreover, the use of the light transmission / reflection mirror in the paper sheet fluorescence detection sensor is advantageous in that the degree of freedom in arranging each component in the housing increases.

Further, the ultraviolet light source and the ultraviolet transmission filter are arranged so as to illuminate the conveyance path of the paper sheet by the light reflected by the light transmission / reflection type mirror, and the light receiving element and the ultraviolet cut filter are the light transmission / reflection. It is preferable to arrange so as to receive the fluorescence transmitted through the mold mirror. In such a configuration, the light reflected from the light transmission / reflection mirror illuminates the paper sheet, and the fluorescence transmitted through the light transmission / reflection mirror is detected by the light receiving element. Is suitable for landscape orientation.

Further, it is preferable to include an illumination monitor housed in the housing and receiving the light emitted from the ultraviolet light source and passing through the light transmission / reflection mirror. The light applied to the paper sheets in the middle of conveyance may not be able to be accurately discriminated (for example, banknote type and authenticity) unless the light sheets are constantly managed in a constant state. In order to solve the problem, the lighting monitor is placed inside the housing.

Further, the ultraviolet light source and the ultraviolet transmission filter are arranged so as to illuminate the conveyance path of the paper sheet with the light transmitted through the light transmission / reflection type mirror, and the light receiving element and the ultraviolet cut filter are provided with the light transmission / reflection. It is preferable to arrange so as to receive the fluorescence reflected by the mold mirror. Such a configuration illuminates the paper sheet with the light passing through the light transmission / reflection type mirror, and detects the fluorescence reflected by the light transmission / reflection type mirror by the light receiving element. Suitable for portrait orientation.

Further, it is preferable to include an illumination monitor which is housed in the housing and receives the light emitted from the ultraviolet light source and reflected by the light transmission / reflection mirror. The light applied to the paper sheets in the middle of conveyance may not be able to be accurately discriminated (for example, banknote type and authenticity) unless the light sheets are constantly managed in a constant state. In order to solve the problem, the lighting monitor is placed inside the housing.

Further, it is preferable that the ultraviolet light source is provided with a lens portion for controlling the light directed to the light transmission / reflection type mirror so that the illumination area is substantially the same as the light receiving area on the transport path. Such a configuration is optimal for effectively utilizing the ultraviolet rays applied to the paper sheets when receiving the fluorescence, and this is easily and surely achieved by providing a lens portion in the ultraviolet light source. .

Further, it is preferable that the light receiving element is provided with a lens portion for controlling the light directed to the light receiving element via the light transmission / reflection type mirror so that the light receiving area is substantially the same as the illumination area on the transport path. Is. Such a configuration is optimal for effectively utilizing the ultraviolet rays applied to the paper sheets when receiving the fluorescence, and this is achieved by providing the lens portion in the light receiving element.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a paper sheet fluorescence detection sensor according to the present invention will be described in detail below with reference to the drawings.

[First Embodiment] FIG. 1 is a sectional view showing a paper sheet inspection device 1. The paper sheet inspection device 1 inspects an example of a paper sheet. It is the authenticity discrimination of a certain banknote, and more specifically, the discrimination between the color-copied forged banknote and the legitimate banknote. This color copy paper has
Since a large amount of fluorescence generating component is contained, attention is paid to this point to make a true / false decision.

The paper sheet inspection device 1 includes an upper and lower guide plates 2,
Linear transport path 4 formed so as to be sandwiched by 3
Is provided, and conveyance rollers 5 and 6 are arranged in the middle of the conveyance path 4, and the bills 7 are formed by the conveyance rollers 5 and 6.
Is reliably transported toward the discharge side. A bill recognition device 8 for identifying a denomination is arranged in the middle of the transport path 4.

Although not shown, the bill (paper sheet) recognition device 8 has a structure in which 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. Then, the image captured by the camera and the known image data are collated to determine the denomination of the bill. However, in recent years, due to the high precision of color copying, it is difficult to determine the authenticity of the bill 7 only by image recognition.

Therefore, the paper sheet fluorescence detection sensor 10 is arranged on the upstream side of the bill recognition device 8. As shown in FIG. 2, the paper sheet fluorescence detection sensor 10 includes a partition part 2 that vertically divides an internal space of a substantially rectangular parallelepiped housing 11 into a vertical direction.
Has 0. This partition 20 is provided with an ultraviolet light source 12
The light receiving element 16 is divided and the inside of the housing 11 is divided into a first compartment 23 and a second compartment 24. Then, in the housing 11, an ultraviolet light source 12 composed of an ultraviolet LED (light emitting element) is housed in the first compartment 23 formed by the partition 20.
Are fixed to the drive circuit board 25 attached to the housing 11 via lead portions 12a bent in an L shape. The ultraviolet light source 12 used here is an ultraviolet lamp containing a visible light component. Also, as a light source, L
The reason for adopting the ED is that the storage space is small even if the housing 11 is small, there are advantages in that there is little variation in brightness, and there is little light fluctuation over time. It is most suitable for the detection sensor 10.

In the second compartment 24, a light receiving element (photo sensor) for detecting the fluorescence emitted from the bill 7
16 is housed, and the light receiving element 16 has a lead portion 16a.
It is fixed to the drive circuit board 25 via. A dustproof glass plate 14 is fixed to the lower surface of the housing 11 with an adhesive or the like so as to close the first compartment 23. The dustproof glass plate 14 is made of glass that easily transmits ultraviolet rays. . The ultraviolet transmission filter 15 arranged in front of the ultraviolet light source 12 is fixed to the wall surface of the opening 20b provided in the first compartment 23 with an adhesive or the like. Therefore, when the light emitted from the ultraviolet LED 12 passes through the ultraviolet transmission filter 15, the ultraviolet component (for example, 3
(About 400 to 400 nm) is emitted from the ultraviolet transmission filter 15. By adopting such an ultraviolet transmission filter 15, the ultraviolet ray content is increased and the light receiving accuracy is improved.

When the fluorescence emitted from the bill 7 is detected using the ultraviolet light source 12 and the light receiving element 16, the bill 7 on the conveying path 4 is not always conveyed in a constant state.
Flapping may occur on the transport path 4, wrinkles S may occur on the banknote 7 itself, or folds P may occur. Even under such a situation, it is necessary to make it difficult to cause unevenness in the output from the light receiving element 16.

Therefore, in order to simultaneously satisfy the application of ultraviolet rays from the direction orthogonal to the transport path 4 and the appropriate reception of the fluorescence from the banknote 7, it is an example of a light transmission / reflection type half mirror. The mirror 30 is used.
The half mirror 30 bends the ultraviolet light emitted from the ultraviolet light source 12 having the optical axis R1 (see FIG. 3) parallel to the transport path 4 by 90 degrees (for example, 45 with respect to the transport path 4). Is fixed to the partition portion 20 so as to close the opening 20a of the partition portion 20 with a certain degree.
As a result, the ultraviolet rays illuminate the banknote 7 with the optical axis R2 (see FIG. 3) that is orthogonal to the transport path 4. Further, the light receiving element 16 is arranged on an extension of the optical axis R2 orthogonal to the transport path 4, and receives the light transmitted through the half mirror 30.

Further, between the half mirror 30 and the light receiving element 16, in front of the light receiving element 16, an ultraviolet cut filter 17 is fixed inside the housing 11 via an adhesive or the like. The reason why such an ultraviolet ray cut filter 17 is used is that if the light transmitted through the half mirror 30 contains an ultraviolet ray component, the light receiving element 16 cannot accurately receive the fluorescent light.

Therefore, when ultraviolet rays are applied from the direction orthogonal to the conveying path 4, it is possible to cope with the fluttering of the banknotes 7 on the conveying path 4, and the banknotes 7 have wrinkles S or folds P. Wrinkle S
The uneven fluorescence caused by suppressing the uneven irradiation of the ultraviolet light in the portion of the fold P is reduced. As a result, it is possible to improve the accuracy of receiving fluorescence. When the banknote 7 illuminated by ultraviolet rays contains a fluorescence-generating component, excited fluorescence is emitted from the banknote 7, and this fluorescence passes through the half mirror 30 along the optical axis R2. It is properly detected by the light receiving element 16.

For example, when the color-copyed counterfeit banknote 7 is fed into the transport path 4, the color-copy sheet contains a large amount of fluorescence-generating components, so the amount of fluorescence detected by the light-receiving element 16 is detected. Will be high. In contrast,
The legitimate bill contains almost no fluorescence-generating component, and the amount of light detected by the light-receiving element 16 is extremely small.
Further, use of such a half mirror 30 makes it possible to reduce the cost of the sensor itself and reduce the manufacturing cost. Moreover, the use of the half mirror (light transmissive / reflective mirror) 30 in the paper sheet fluorescence detection sensor 10 makes it possible to arrange each component in the housing 11, for example, the ultraviolet light source 12 or the light receiving element 16. It is advantageous in that it increases.

Further, the amount of light applied to the banknotes 7 being conveyed may not be accurately inspected (for example, banknote type and authenticity) unless the amount of light applied is kept constant. Therefore, as one of the means for managing it, the illumination monitor 18 including a photosensor receives the light passing through the half mirror 30. This lighting monitor 18 is used for the second compartment 2
4 and is arranged on an extension of the optical axis R1 (see FIG. 3). The illumination monitor 18 is fixed to the drive circuit board 25 via the lead portion 18a.
Therefore, the light emitted from the ultraviolet light source 12 is indirectly received by the illumination monitor 18 through the half mirror 30.

Further, when the ultraviolet rays applied to the bill 7 are effectively used, it is preferable that the illumination area A and the light receiving area B are substantially the same on the transport path 4 (see FIG. 3). Therefore, the lens portion 33 is provided at the tip of the ultraviolet LED 12.
When the light receiving area B is known in advance, the lens portion 33 is used for adjusting the illumination angle of the ultraviolet LED 12 to control the light toward the half mirror 30, and the optimum brightness has the optimum light receiving area B. UV LED as obtained in
Various selections are made according to the 12 characteristics. By using the lens unit 33 as described above, the illumination angle of the ultraviolet LED 12 can be adjusted.

As shown in FIG. 4, as another paper sheet fluorescence detecting sensor 40, when the ultraviolet rays applied to the bill 7 are effectively used, the illumination area A and the light receiving area B are substantially omitted on the transport path 4. For the same purpose, the ultraviolet light cut filter 17 may be sandwiched between the light receiving element 16 and the lens portion 35. The lens portion 35 is used for adjusting the light receiving angle of the light receiving element 16 and controlling the fluorescence that passes through the half mirror 30 and goes toward the light receiving element 16 when the illumination area A is known in advance. And the lens unit 3
5 is a light receiving element 1 so that an optimum light receiving region B can be obtained.
Variously selected according to the characteristics of 6. By using the lens unit 35 as described above, the optimum light receiving region B can be created.

Further, when the ultraviolet light source 12 having high directivity is used, the lens portion 33 is not necessary. Further, the lens portion 33 may be arranged in front of the ultraviolet light source 12 and the lens portion 35 may be arranged in front of the light receiving element 16. Further, as an example of the light transmission / reflection mirror 30, a half mirror having a light transmission / light reflection ratio of 5: 5 has been described as an example, but the relationship between the brightness of the ultraviolet light source 12 and the sensitivity of the light receiving element 16 It goes without saying that various ratios are selected in.

[Second Embodiment] The present invention is not limited to the above-described first embodiment. As shown in FIG. 5, the paper sheet fluorescence detection sensor 50 includes a partition portion 60 that vertically divides an internal space of a substantially rectangular parallelepiped housing 51.
have. The partition portion 60 separates the ultraviolet light source 52 and the light receiving element 56 from each other, and the first inside of the housing 51 is separated.
It is divided into a compartment 63 and a second compartment 64. In the housing 51, an ultraviolet light source 52 composed of an ultraviolet LED (light emitting element) is housed in the first compartment 63 formed by the partition portion 60.
Are fixed to the drive circuit board 65 attached to the housing 51 so as to be suspended via the lead portions 52a.

The ultraviolet light source 52 used here is an ultraviolet LED containing a visible light component. Further, the reason why the LED is adopted as the light source is that the housing 51 has a small accommodation space even if the housing 51 is small, has a small variation in brightness, and has a small light fluctuation with time. Paper sheet fluorescence detection sensor 50
Is perfect for.

In the second compartment 64, a light receiving element (photo sensor) for detecting the fluorescence emitted from the bill 7
56 is accommodated, and the light receiving element 56 includes a lead portion 56a.
It is fixed so as to be hung on the drive circuit board 65 via. Further, a dustproof glass plate 54 is fixed to the lower surface of the housing 51 with an adhesive or the like so as to close the second compartment 64,
The dustproof glass plate 54 is made of glass that easily transmits ultraviolet rays. Further, the ultraviolet transmission filter 53 arranged in front of the ultraviolet light source 52 is fixed to the partition part 60 with an adhesive or the like. Therefore, the UV LED 5
The light emitted from No. 2 passes through the ultraviolet transmission filter 53, so that the ultraviolet component (for example, 300 to 400 n) is obtained.
m) is emitted from the ultraviolet transmission filter 53. By adopting such an ultraviolet transmission filter 53, the ultraviolet ray content is increased and the light receiving accuracy is improved.

Further, the ultraviolet LED 52 and the dustproof glass plate 5
A half mirror 55, which is an example of a light transmission / reflection type mirror, is fixed to the partition 60 by an adhesive or the like so as to close the opening 60a of the partition 60 provided between the partition 60 and the partition 60. The half mirror 55 has a relationship of 5: 5 in the ratio of light transmission and light reflection. Therefore, the light emitted from the ultraviolet transmission filter 53 (for example, 300 to 4)
(About 00 nm) simply passes through the half mirror 55 and is emitted toward the dustproof glass plate 54.

When the fluorescence emitted from the bill 7 is detected using the ultraviolet light source 52 and the light receiving element 56, the bill 7 on the conveying path 4 is not always conveyed in a constant state.
Flapping may occur on the transport path 4, wrinkles S may occur on the banknote 7 itself, or folds P may occur. Even under such a situation, it is necessary to make it difficult to cause unevenness in the output from the light receiving element 56.

Therefore, the half mirror 55 described above is used in order to simultaneously satisfy the application of the ultraviolet rays from the direction orthogonal to the transport path 4 and the appropriate reception of the fluorescence from the banknote 7. This half mirror 55
Is disposed between the ultraviolet light source 52 and the dustproof glass plate 54, and the ultraviolet light source 52 is oriented such that its optical axis R1 (see FIG. 6) is orthogonal to the transport path 4. Further, the half mirror 55 has an angle (for example, 45 degrees with respect to the conveyance path 4) that reflects fluorescence emitted from the banknote 7 by ultraviolet irradiation toward the light receiving element 56 by 90 degrees, and the partition section of the housing 51. It is fixed at 60. That is, the reflecting surface of the half mirror 55 is located on the intersection point where the optical axis R2 of the light receiving element 56 and the optical axis R1 of the ultraviolet light source 52 are orthogonal to each other, and the optical axis R1 is orthogonal to the transport path 4.

An ultraviolet cut filter 57 is attached to the light receiving element 56 between the half mirror 55 and the light receiving element 56. The reason why such an ultraviolet ray cut filter 57 is adopted is that the light that is about to enter the light receiving element 56 may contain a relatively large amount of ultraviolet ray components, and the excess ultraviolet ray components are cut to improve the light receiving accuracy. This is to improve.

Therefore, when ultraviolet rays are applied from the direction orthogonal to the conveying path 4, it is possible to deal with the fluttering of the banknotes 7 on the conveying path 4, and the banknotes 7 have wrinkles S or folds P. Wrinkle S
The unevenness of fluorescence caused by suppressing the unevenness of irradiation with ultraviolet light does not occur in the part of the fold P. As a result, it is possible to improve the accuracy of receiving fluorescence. When the banknote 7 illuminated by the ultraviolet rays contains a fluorescence-generating component, excited fluorescence is emitted from the banknote 7, and the fluorescence is reflected by the half mirror 55 along the optical axis R1. , Is properly detected by the light receiving element 56 along the optical axis R2.

For example, when the color-copied counterfeit bill 7 is fed into the conveyance path 4, the color copy paper contains a large amount of fluorescence-generating components, and therefore the amount of fluorescence detected by the light-receiving element 56 is detected. Will be high. In contrast,
A legitimate bill contains almost no fluorescence-generating component, and the amount detected by the light-receiving element 56 is extremely small. Further, the use of such a half mirror 55 makes the sensor itself inexpensive and enables reduction in manufacturing cost.
Moreover, the use of the half mirror (light transmission / reflection type mirror) 55 in the paper sheet fluorescence detection sensor 50 allows the degree of freedom in the arrangement of each component in the housing 51, for example, the ultraviolet light source 52 and the light receiving element 56. It is advantageous in that it increases.

Further, the amount of light applied to the banknotes 7 being conveyed may not be accurately inspected (for example, banknote type and authenticity) unless the amount of light applied to the banknotes 7 is constantly controlled. Therefore, as one means of managing the light, the illumination monitor 58 including a photosensor receives the light reflected by the half mirror 55. The illumination monitor 58 is housed in the first compartment 63 and is arranged on the extension of the optical axis R2 (see FIG. 6) to reliably capture the visible light reflected by the half mirror 55. The illumination monitor 58 is fixed to the drive circuit board 65 via the lead portion 58a. Therefore, the light emitted from the ultraviolet light source 52 is reflected by the half mirror 55 and indirectly received by the illumination monitor 58.

Further, when the ultraviolet rays applied to the bill 7 in the state as shown in FIG. 5 are effectively utilized, it is preferable that the illumination area A and the light receiving area B are substantially the same on the transport path 4 (FIG. 6). Therefore, the lens portion 73 is provided at the tip of the ultraviolet LED 52. When the light receiving area B is known in advance, the lens portion 73 is used for adjusting the illumination angle of the ultraviolet LED 52 and controlling the light traveling toward the transport path 4, and the optimum brightness is the light receiving area. As shown in B, various selections are made according to the characteristics of the ultraviolet LED 52. By using the lens portion 73 as described above, the ultraviolet rays L
The illumination angle of the ED 52 can be adjusted.

The present invention is not limited to the above embodiment. For example, another paper sheet fluorescence detection sensor 80
Then, as shown in FIG. 7, in order to effectively use the ultraviolet rays applied to the banknote 7 (see FIG. 5), in order to make the illumination area A and the light receiving area B substantially the same on the transport path 4, The ultraviolet cut filter 57 is sandwiched between the element 56 and the lens portion 75. This lens part 75
Is the light receiving element 5 when the illumination area A is known in advance.
It is used to adjust the light receiving angle of 6 and control the fluorescence toward the light receiving portion of the light receiving element 56. Then, the lens portion 75 is variously selected according to the characteristics of the light receiving element 56 so that the optimum light receiving region B can be obtained. By using such a lens part 75, an optimum light receiving area B can be created.

Further, when the ultraviolet light source 52 having high directivity is used, the lens portion 73 is not necessary. Further, the lens portion 73 may be arranged in the front so as to be separated from the ultraviolet light source 52, and the lens portion 75 may be arranged in the front so as to be separated from the light receiving element 56. Further, as an example of the light transmission / reflection mirror 55, the half mirror having a light transmission / light reflection ratio of 5: 5 has been described, but the relationship between the brightness of the ultraviolet light source 52 and the sensitivity of the light receiving element 56 is described. It goes without saying that various ratios are selected in.

[0041]

The paper sheet fluorescence detection sensor according to the present invention comprises:
Since it is configured as described above, the following effects are obtained. That is, in the course of transporting the paper sheet, in the paper sheet fluorescence detection sensor that irradiates the paper sheet with light and detects the fluorescence emitted from the paper sheet, the ultraviolet light source housed in the housing and the inside of the housing. An ultraviolet transmission filter that is housed and arranged in front of the ultraviolet light source, and that is housed in the housing and that transmits and reflects light that has passed through the ultraviolet transmission filter and is orthogonal to the paper sheet conveyance path. A light transmission / reflection mirror that shines light, and is housed in the housing,
By providing a light receiving element that receives fluorescence emitted from paper sheets by irradiation of ultraviolet rays through a light transmission / reflection type mirror, and an ultraviolet cut filter arranged between the light receiving element and the light transmission / reflection type mirror. To realize a paper sheet fluorescence detection sensor that accurately receives fluorescence emitted from paper sheets and is not easily affected by the state of the paper sheet.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a paper sheet inspection device to which a paper sheet fluorescence detection sensor according to the present invention is applied.

FIG. 2 is a sectional view showing a first embodiment of a paper sheet fluorescence detection sensor according to the present invention.

3 is a cross-sectional view showing an illumination region and a light receiving region of the sensor shown in FIG.

FIG. 4 is a cross-sectional view showing a modified example of the paper sheet fluorescence detection sensor shown in FIG.

FIG. 5 is a sectional view showing a second embodiment of the paper sheet fluorescence detection sensor according to the present invention.

6 is a cross-sectional view showing an illumination region and a light receiving region of the sensor shown in FIG.

7 is a cross-sectional view showing a modified example of the paper sheet fluorescence detection sensor shown in FIG.

[Explanation of symbols]

4 ... Transport path, 7 ... Banknotes (paper sheets) 10, 40, 5
0,80 ... Fluorescence detection sensor for paper sheets, 11,51 ... Casing,
12, 52 ... Ultraviolet LED (ultraviolet light source), 15, 53
... Ultraviolet transmission filter, 16, 56 ... Light receiving element, 17,
57 ... Ultraviolet ray cut filter, 18, 58 ... Illumination monitor, 30, 55 ... Half mirror (light transmission / reflection type mirror), 33, 35, 73, 75 ... Lens part, A ... Illumination area, B ... Light receiving area, R1 , R2 ... Optical axis.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazunori Hirose             2-18-10 Shimura, Itabashi-ku, Tokyo Nidec             Sankopal Co., Ltd. (72) Inventor Mitsuyo Usami             2-18-10 Shimura, Itabashi-ku, Tokyo Nidec             Sankopal Co., Ltd. F-term (reference) 3E041 AA02 BB03 BB04 BB05 EA01

Claims (7)

[Claims] 1. A paper sheet fluorescence detection sensor for irradiating the paper sheet with light during transportation of the paper sheet to detect fluorescence emitted from the paper sheet, wherein the ultraviolet light source is housed in a housing. An ultraviolet transmission filter housed in the housing and arranged in front of the ultraviolet light source; and an ultraviolet transmission filter housed in the housing and transmitting and reflecting light passing through the ultraviolet transmission filter, A light-transmissive / reflective mirror that irradiates light that is orthogonal to the transport path of the class, and is housed in the housing, and emits fluorescence emitted from the paper sheet by irradiation of ultraviolet rays to the light-transmissive / reflective mirror A paper sheet fluorescence detection sensor, comprising: a light receiving element that receives light via an ultraviolet ray cut filter disposed between the light receiving element and the light transmission / reflection mirror. 2. The ultraviolet light source and the ultraviolet transmission filter are arranged so as to illuminate the conveyance path of the paper sheet with the light reflected by the light transmission / reflection type mirror,
The paper sheet fluorescence detection sensor according to claim 1, wherein the light receiving element and the ultraviolet cut filter are arranged so as to receive the fluorescence transmitted through the light transmission / reflection mirror. 3. The illumination monitor according to claim 2, further comprising an illumination monitor which is housed in the housing and receives light emitted from the ultraviolet light source and passing through the light transmission / reflection mirror. Paper sheet fluorescence detection sensor. 4. The ultraviolet light source and the ultraviolet transmission filter are arranged so as to illuminate the conveyance path of the paper sheet with the light transmitted through the light transmission / reflection type mirror,
2. The paper sheet fluorescence detection sensor according to claim 1, wherein the light receiving element and the ultraviolet cut filter are arranged so as to receive the fluorescence reflected by the light transmission / reflection mirror. 5. The illumination monitor according to claim 4, further comprising an illumination monitor that is housed in the housing and receives light emitted from the ultraviolet light source and reflected by the light transmission / reflection mirror. Paper sheet fluorescence detection sensor. 6. The ultraviolet light source is provided with a lens unit for controlling light directed to the light transmission / reflection mirror so that the illumination area is substantially the same as the light receiving area on the transport path. The paper sheet fluorescence detection sensor according to any one of claims 1 to 5. 7. A lens unit for controlling light directed to the light receiving element via the light transmission / reflection mirror so that the light receiving element has a light receiving area substantially the same as an illumination area on the transport path. It is provided with 1.
6. The paper sheet fluorescence detection sensor according to claim 6.