JP7089886B2 - Identification device - Google Patents

Description

The present invention relates to an identification device.

Patent Document 1 describes a technique relating to a coin discriminating device for a coin processing machine. The coin discriminating device described in this document receives a plurality of light emitting elements such as LEDs that irradiate light toward one surface of a coin being transported, and light reflected on one surface of the coin, and has an image pattern. A light receiving means for generating data is provided. The plurality of light emitting elements are arranged on a circle centered on the central portion of the transparent passage portion. Each light emitting element is arranged so that the optical axis forms a small angle with respect to the horizontal direction and faces a predetermined point on the central axis of the circle centered on the center of the transparent passage portion. It is possible to irradiate the coins passing over the part with light at a shallow angle.

Patent Document 2 describes a technique relating to a coin identification device. The coin identification device described in this document includes an image input unit that captures an image of the surface of the coin to be identified and generates imaging data on the surface, an identification unit that identifies the type of the coin to be identified based on the imaging data, and an identification unit. To prepare for. A transparent plate having an opening is provided between the transport path for transporting coins and the image pickup apparatus, and a light emitting element is arranged around the opening inside the transparent plate. The light emitting element is, for example, an infrared LED.

Japanese Unexamined Patent Publication No. 2011-197865 Japanese Unexamined Patent Publication No. 2005-284918

A recent identification device captures an image of an object to be identified in order to identify the authenticity and type of, for example, coins, banknotes, medals, tokens, etc., and performs identification based on the obtained imaging data. When imaging an object to be identified, it is necessary to illuminate the imaged surface of the object to be identified. At that time, in order to prevent the reflected light from the image-receiving surface from entering the image pickup apparatus, the light is irradiated from the periphery of the image-image surface at a shallow angle (see, for example, Patent Documents 1 and 2).

When irradiating the surface to be imaged with light, it is desirable to irradiate uniform light with suppressed luminance unevenness. This is because by irradiating with uniform light, more accurate imaging data can be acquired and the identification accuracy can be improved. Therefore, for example, a method of increasing the arrangement density of the light emitting element or increasing the distance from the light emitting element to the object to diffuse the light can be considered. However, if the arrangement density of the light emitting elements is increased, the number of light emitting elements increases and the manufacturing cost increases. Further, if the distance from the light emitting element to the object is increased, the miniaturization of the identification device is hindered.

The present invention has been made in view of such problems, and an object of the present invention is to provide an identification device capable of irradiating an object to be identified with uniform light while suppressing manufacturing costs and realizing miniaturization. And.

In order to solve the above-mentioned problems, the identification device according to the present invention is a device that identifies an identification object based on its appearance, and is an image input unit that captures an image of the identification object and generates imaging data regarding the identification object. And an identification processing unit that identifies an object to be identified based on the image pickup data. The image input unit has an image pickup means for imaging the identification object and a light irradiation means for illuminating the identification object, and the light irradiation means has a cylindrical shape extending in a direction in which the central axis intersects the imaged surface of the identification object. It has a translucent member and a light emitting portion that incidents light into the translucent member. The outer surface of the translucent member has a first region inclined with respect to the central axis so that the closer to the end on the identification object side, the closer to the central axis, and the distance between the first region and the central axis is constant along the above direction. Includes 2 regions . The distance between the inner surface of the translucent member and the central axis is constant along the above direction. The light emitting portion injects light into the translucent member from an end portion of the translucent member opposite to the object to be identified in the above direction. The light incident on the translucent member from the end portion travels along the above direction while being confined between the inner side surface and the second region, and reaches the first region. The first region reflects and diffuses the light towards the object to be identified. The image pickup means receives light that is reflected by the object to be identified and passes through the inside of the translucent member.

In this identification device, light is incident from a light emitting portion into a cylindrical translucent member. The light propagates in the translucent member and reaches the inclined region of the outer surface. This region reflects and diffuses the light propagating inside the translucent member toward the identification object passing through the region extending the inner surface of the cylinder. The reflected and diffused light is emitted from the inner side surface of the translucent member to the outside of the transmissive member, and is irradiated on the imaged surface of the object to be identified. According to the identification device having such a configuration, uniform light can be applied to the identification object. Further, since the light is diffused by the translucent member, the number of light emitting elements can be suppressed even when the light emitting unit is composed of a plurality of light emitting elements, for example. Therefore, the manufacturing cost can be suppressed. Further, since the distance from the light emitting element to the object can be shortened, the size of the identification device can be reduced.

Further, in the above-mentioned identification device, the above-mentioned region may form a side surface of an imaginary conical table having a central axis as the central axis. This makes it possible to effectively diffuse the light and improve the uniformity.

Further, in the above-mentioned identification device, the light emitting portion may inject light into the translucent member from an end portion of the translucent member opposite to the object to be identified in the above-mentioned direction. As a result, the propagation distance of light inside the translucent member can be sufficiently secured, and the degree of diffusion can be further increased.

Further, in the above-mentioned identification device, the above-mentioned region of the translucent member may be subjected to light diffusion processing. Alternatively, in the above-mentioned identification device, a light-diffusing member may be attached to the above-mentioned region of the light-transmitting member. Alternatively, in the above-mentioned identification device, a light diffusion film may be applied to the above-mentioned region of the translucent member. By providing the identification device with at least one of these configurations, it is possible to effectively diffuse the light and improve the uniformity.

Further, in the above-mentioned identification device, the translucent member may be made of resin. Thereby, the above-mentioned shape of the translucent member can be easily realized.

Further, in the above-mentioned identification device, the identification object may be a coin or a medal. Since these have a substantially circular imaged surface, a special effect can be obtained in the above-mentioned identification device provided with a cylindrical translucent member.

According to the identification device according to the present invention, it is possible to irradiate the identification object with uniform light while suppressing the manufacturing cost and realizing miniaturization.

It is a block diagram schematically showing the structure of the identification apparatus 1 which concerns on one Embodiment of this invention. It is sectional drawing which shows the specific structural example of the image input unit 2. It is a perspective view which shows the appearance of a translucent member 22. (A) It is a figure which shows the example which light diffusion processing is applied to the region 22c. (B) It is a figure which shows the example which the light diffusing member 26 is attached to the region 22c. (C) It is a figure which shows the example which the light diffusing film 27 is applied to the region 22c.

Hereinafter, embodiments of the identification device according to the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 1 is a block diagram schematically showing a configuration of an identification device 1 according to an embodiment of the present invention. The identification device 1 of the present embodiment is a device that identifies the authenticity and type of the identification object based on the appearance. Examples of the identification target include coins, commemorative coins, medals, tokens, paper leaves such as banknotes, and plate-shaped objects such as cards. As shown in FIG. 1, the identification device 1 of the present embodiment includes an image input unit 2, an identification processing unit 3, and a control unit 4. The image input unit 2 takes an image of the surface of the identification object and generates imaging data regarding the surface of the identification object. The identification processing unit 3 identifies the authenticity and type of the identification object based on the image pickup data. The identification processing unit 3 has a processing unit 31, a storage unit 32, and a comparison unit 33. The processing unit 31 inputs the image pickup data from the image input unit 2 and processes the image pickup data in a format suitable for identification. Further, the storage unit 32 stores in advance data that serves as a reference for identification (hereinafter referred to as reference data). The storage unit 32 is configured by an electronic storage means such as a memory. The comparison unit 33 identifies the authenticity and type of the identification target object by comparing the processed image data output from the processing unit 31 with the reference data stored in the storage unit 32. The processing unit 31 and the comparison unit 33 have an arithmetic processing device such as a CPU and a storage means such as a memory, and are preferably realized by a computer operated by the arithmetic processing apparatus reading a program stored in the storage means. Alternatively, the processing unit 31 and the comparison unit 33 may be realized by a hardware chip such as an ASIC. The processing unit 31 and the comparison unit 33 may be realized by a common computer or a hardware chip, or may be realized by a separate computer or a hardware chip. Further, the storage means of the processing unit 31 and the comparison unit 33 may be common to the storage means of the storage unit 32, or may be provided separately from each other.

The control unit 4 controls the image input unit 2 and the identification processing unit 3. Specifically, an image pickup timing sensor (not shown) is provided in the transport path of the identification object, and the image pickup timing sensor sends an electrical passage signal indicating the passage of the identification object to the control unit 4. Based on this passing signal, the control unit 4 controls the operation of the image input unit 2 so as to image the identification object at a good timing. Further, the identification processing unit 3 is controlled so as to perform the above-mentioned identification operation according to the timing. The image pickup timing sensor is arranged upstream of the image input unit 2 in the transport path.

FIG. 2 is a cross-sectional view showing a specific configuration example of the image input unit 2. As shown in FIG. 2, the image input unit 2 has a light irradiation means 20 that illuminates the identification object 5 and an image pickup means 25 that images the identification object 5. The image input unit 2 is arranged along a transport path which is a gap in which the identification target object 5 is transported, and is provided on the side opposite to the identification target object 5 with respect to the translucent plate 21 forming a part of the transport surface. Be done. The translucent plate 21 is a plate-shaped member that closes a circular opening formed in a part of the transport surface, and is in a wavelength range including at least the wavelength of light irradiated to the identification object 5 by the light irradiation means 20. Has light transmission characteristics. The translucent plate 21 is made of, for example, glass or resin. In one embodiment, the translucent plate 21 is made of sapphire glass. In the present embodiment, the identification object 5 moves on the translucent plate 21, and at that time, the imaged surface 5a of the identification object 5 faces one plate surface 21a of the translucent plate 21. The normal of the plate surface 21a is along the vertical direction.

The image pickup means 25 is composed of an image pickup device such as a CCD and a CCD camera including a lens. The image pickup means 25 is arranged so as to face the imaged surface 5a of the identification object 5 with the translucent plate 21 interposed therebetween. In other words, the image pickup means 25 is arranged below the translucent plate 21 so as to face the plate surface 21b on the side opposite to the plate surface 21a of the translucent plate 21. The image pickup means 25 is controlled by the above-mentioned control unit 4 (see FIG. 1), and images the imaged surface 5a at the moment when the identification object 5 passes in front of the image pickup means 25.

The light irradiating means 20 has a light transmitting member (light guide member) 22 and a light emitting unit 23. The light emitting unit 23 injects light L into the translucent member 22. The light L is emitted from all the light emitting units 23 at the same time, but for ease of understanding, only the light L from a part of the light emitting units 23 is shown in FIG. The light emitting unit 23 is preferably configured by, for example, a plurality of light emitting elements mounted on the mounting surface 24a of the substrate 24. The light emitting element is, for example, an LED. The light emitting element may be either a surface mount type or a lead type, or a combination thereof may be used. The wavelength of the light L output from the light emitting unit 23 is arbitrarily determined, but for example, the infrared region or the visible region is suitable for clearly capturing the shape and pattern of the image-receiving surface 5a. The mounting surface 24a extends along the plate surface 21a of the translucent plate 21 (that is, along the horizontal plane). The substrate 24 has a circular opening 24b for allowing the surface to be imaged 5a to be seen from the image pickup means 25. The opening 24b is formed at a position overlapping the image pickup means 25 when viewed from the normal direction of the plate surface 21a. A plurality of light emitting elements constituting the light emitting unit 23 are arranged in an annular shape along the peripheral edge portion of the opening 24b. These light emitting elements emit light L along the direction A1 with the optical axis direction directed toward the transport path. In this case, since the light emitting element may be mounted on the substrate 24 so as to emit light L in the direction perpendicular to the mounting surface 24a, the mounting work of the light emitting element becomes relatively easy.

The light transmitting member 22 has a light transmitting characteristic in a wavelength range including at least the wavelength of the light L emitted from the light emitting unit 23. The translucent member 22 is made of, for example, glass or resin. In one embodiment, the translucent member 22 is made of a transparent resin.

FIG. 3 is a perspective view showing the appearance of the translucent member 22. As shown in FIGS. 2 and 3, the translucent member 22 has a cylindrical shape, and its central axis C1 is along a direction A1 that intersects (for example, is orthogonal to) the imaged surface 5a of the identification object 5. Is extending. The direction A1 intersects the plate surface 21a of the translucent plate 21 and is orthogonal to, for example. The translucent member 22 has an inner side surface 22a, an outer side surface 22b, and an end surface 22d. The cross-sectional shapes of the inner side surface 22a and the outer side surface 22b in the cross section perpendicular to the central axis C1 are both circular. The distance between the inner side surface 22a and the central axis C1 is constant along the direction A1. On the other hand, the distance between the outer surface 22b and the central axis C1 is constant along the direction A1 except for a part of the region 22c. That is, the outer surface 22b excluding a part of the region 22c forms a cylindrical surface. The image pickup means 25 is located inside an imaginary cylinder having an inner side surface 22a extended on the side opposite to the transport path.

A part of the region 22c of the outer side surface 22b is inclined with respect to the direction A1 so as to be closer to the central axis C1 as it approaches the end on the identification target 5 side (that is, the end on the transport path side) 22e. When the central axis C1 is perpendicular to the plate surface 21a of the translucent plate 21, the region 22c is also inclined with respect to the plate surface 21a. In one example, the region 22c forms the side surface of an imaginary conical table with the central axis C1 as the central axis. The region 22c reflects and diffuses the light L output from the light emitting unit 23 and propagating in the translucent member 22 toward the identification object 5. That is, the region 22c reflects the light propagating in the translucent member 22 due to the difference in the refractive index between the translucent member 22 and its external medium (air). Therefore, it is preferable that the angle formed by the extending direction (direction A1) of the translucent member 22 and the region 22c is an angle at which the light L can be totally reflected in the region 22c. The angle θ formed by the direction A1 and the region 22c is, for example, in the range of 40 ° to 44 °.

Further, the region 22c has a structure for diffusing the light L at the time of its reflection. For example, as shown in FIG. 4A, the region 22c is light-diffused. The light diffusion processing may be, for example, frosted glass processing for forming fine irregularities on the surface, rough surface processing, or processing for arranging a plurality of fine lens shapes in a two-dimensional manner. Alternatively, as shown in FIG. 4B, the light diffusing member 26 may be attached to the region 22c. Alternatively, as shown in FIG. 4C, the light diffusing film 27 may be applied to the region 22c. As the structure for diffusing the light L, the configurations shown in FIGS. 4 (a) to 4 (c) may be used alone, or at least two of these configurations may be combined in combination. May be good. The region 22c may be connected to the inner side surface 22a or may be separated from the inner side surface 22a. Further, the region 22c may or may not reach the end 22e of the translucent member 22 on the identification object 5 side.

The end surface 22d is a surface located at the end of the translucent member 22 in the direction A1 opposite to the identification object 5 (that is, the end opposite to the transport path). The end face 22d is flat and runs along an imaginary plane that intersects (in one example, is orthogonal) the central axis C1. The end surface 22d faces the mounting surface 24a of the substrate 24, and the light L emitted from the light emitting unit 23 is incident on the inside of the translucent member 22 from the end surface 22d. The light emitting elements of the light emitting unit 23 and the end face 22d may be in contact with each other or may be separated from each other. Further, each light emitting element of the light emitting unit 23 and the end face 22d may or may not be fixed to each other. A refractive index matching material may be interposed between each light emitting element of the light emitting unit 23 and the end face 22d.

The operation of the identification device 1 of the present embodiment having the above configuration will be described. First, the identification object 5 is inserted into the input port of the identification device 1. The identification object 5 is transported on the transport surface of the transport path by a transport means (for example, a drive belt or the like). Then, the image pickup timing sensor detects that the identification object 5 has been conveyed to a predetermined position. The image pickup timing sensor outputs a detection signal to the control unit 4. The control unit 4 causes the light emitting unit 23 to emit light for a predetermined time based on the detection signal.

The light L emitted from the light emitting unit 23 is incident on the translucent member 22 from the end surface 22d, and travels along the extending direction (direction A1) of the translucent member 22 while spreading. At this time, the light L is confined between the inner surface 22a and the outer surface 22b due to the difference in refractive index between the translucent member 22 and the external medium (air). Further, at this time, the light L expands greatly as the distance between the end face 22d and the region 22c becomes longer. Then, when the light L reaches the region 22c, the light L is reflected and diffused toward the identification object 5, and is emitted from the inner side surface 22a to the outside of the translucent member 22. At this time, the optical axis of the light L before reflection and the optical axis of the light L after reflection (diffuse) so that the light L faces the imaged surface 5a of the identification object 5 arranged above the translucent member 22. It forms an angle larger than 90 ° with the center of light). In other words, the incident angle of the light L with respect to the region 22c is larger than 45 °. Further, since the incident angle of the light L with respect to the inner side surface 22a is sufficiently large, most of the light L passes through the inner side surface 22a.

The identification object 5 passes through the image input unit 2 while being illuminated by the light L. When the identification object 5 passes through the image input unit 2, the image pickup means 25 performs imaging at the timing when the identification object 5 passes through the fictitious cylinder in which the inner side surface 22a of the translucent member 22 extends toward the transport path side. As described above, the control unit 4 controls the image pickup means 25. At this time, the image pickup means 25 receives the light L that is reflected on the imaged surface 5a of the identification object 5 and passes through the inside of the translucent member 22 (that is, the region surrounded by the inner side surface 22a). The image pickup data relating to the imaged surface 5a generated by the image pickup means 25 is sent to the identification processing unit 3. In the identification processing unit 3, the processing unit 31 appropriately processes the imaging data to create the processed data. The created processed data is input to the comparison unit 33 together with the reference data stored in the storage unit 32 in advance. The comparison unit 33 compares the processed data with the reference data, determines whether or not the identification object 5 conforms to the identification criteria, and outputs the result.

The effect obtained by the identification device 1 according to the present embodiment described above will be described. As described above, in the identification device 1, the light L is incident from the light emitting unit 23 in the cylindrical translucent member 22. The light L propagates in the translucent member 22 and reaches the inclined region 22c of the outer surface 22b. This region 22c reflects and diffuses the light L propagating inside the translucent member 22 toward the identification object 5 passing through the inside of the cylinder extending the inner side surface 22a. The reflected and diffused light L is emitted from the inner side surface 22a to the outside of the translucent member 22, and is irradiated on the image-received surface 5a of the identification object 5. According to such a configuration, the light L can be irradiated from a direction inclined with respect to the normal direction of the image-receiving surface 5a. Further, the light L spreads over a wide range from the vicinity of the inner side surface 22a to a long distance, and the density of the light L in the irradiation range is made uniform by diffusion. Then, since the light transmitting member 22 is arranged so as to surround the imaged surface 5a, such light L is irradiated from the entire periphery of the imaged surface 5a. Therefore, according to this identification device 1, uniform light L can be applied to the identification object 5. Further, since the light L is diffused by the light transmitting member 22, the number of light emitting elements can be suppressed even when the light emitting unit 23 is composed of a plurality of light emitting elements, for example. Therefore, the manufacturing cost can be suppressed. Further, since the distance from the light emitting unit 23 to the identification object 5 can be shortened, the identification device 1 can be miniaturized.

Further, as in the present embodiment, the region 22c may form a side surface of an imaginary conical table having the central axis C1 of the translucent member 22 as the central axis. As a result, the light L can be effectively diffused to improve the uniformity.

Further, as in the present embodiment, the light emitting unit 23 injects light L into the translucent member 22 from the end portion (end surface 22d) of the translucent member 22 on the opposite side of the identification object 5 in the direction A1. May be good. As a result, the propagation distance of light inside the translucent member 22 can be sufficiently secured, and the degree of diffusion can be further increased.

Further, as in the present embodiment, the region 22c of the translucent member 22 may be light-diffused. Alternatively, the light diffusing member 26 may be attached to the region 22c of the light transmitting member 22. Alternatively, the light diffusing film 27 may be applied to the region 22c of the light transmissive member 22. By providing the identification device 1 with at least one of these configurations, the light L can be effectively diffused and the uniformity can be enhanced.

Further, as in the present embodiment, the translucent member 22 may be made of resin. Thereby, the above-mentioned shape of the translucent member 22 can be easily realized.

Further, as in the present embodiment, the identification object 5 may be a coin or a medal. Since these have a substantially circular imaged surface 5a, a special effect can be obtained in the identification device 1 provided with the cylindrical translucent member 22.

The identification device according to the present invention is not limited to the above-described embodiment, and various other modifications are possible. For example, in the above embodiment, a light emitting unit 23 in which a plurality of light emitting elements are arranged in an annular shape is exemplified, but the configuration of the light emitting unit 23 is not limited to this, and for example, a single light emitting unit having an annular light emitting region. It may be configured by a light emitting device. Further, in the above embodiment, the light diffusing process, the light diffusing member 26, and the light diffusing film 27 are exemplified as means for diffusing the light L in the region 22c of the outer surface 22b, but the means for diffusing the light L in the region 22c. Is not limited to these.

1 ... Identification device, 2 ... Image input unit, 3 ... Identification processing unit, 4 ... Control unit, 5 ... Identification object, 5a ... Image-imposed surface, 20 ... Light irradiation means, 21 ... Translucent plate, 21a, 21b ... Plate surface, 22 ... Translucent member, 22a ... Inner surface, 22b ... Outer surface, 22c ... Region, 22d ... End surface, 22e ... End, 23 ... Light emitting part, 24 ... Board, 24a ... Mounting surface, 24b ... Opening, 25 ... Imaging means, 26 ... Light diffusing member, 27 ... Light diffusing film, 31 ... Processing unit, 32 ... Storage unit, 33 ... Comparison unit, A1 ... Direction, C1 ... Central axis, L ... Light.

Claims (7)

A device that identifies an object to be identified based on its appearance.
An image input unit that captures an image of the identification object and generates imaging data related to the identification object.
An identification processing unit for identifying the identification object based on the imaging data is provided.
The image input unit has an image pickup means for imaging the identification object and a light irradiation means for illuminating the identification object.
The light irradiating means has a cylindrical light-transmitting member extending in a direction in which the central axis intersects the image-receiving surface of the identification object, and a light-emitting portion that incidents light into the light-transmitting member.
The outer surface of the translucent member has a distance between the central axis and the first region inclined with respect to the central axis so that the closer to the end on the identification object side, the closer to the central axis. The distance between the inner surface of the translucent member and the central axis is constant along the direction, including the second region which is constant.
The light emitting portion incidents light into the translucent member from the end of the translucent member opposite to the identification object in the direction, and the light incident on the translucent member from the end thereof. , Confined between the inner surface and the second region, travels along the direction to reach the first region, where the first region reflects and reflects the light towards the identification object. Spread and
The image pickup means is an identification device that receives light that is reflected by the identification object and passes through the inside of the translucent member. The identification device according to claim 1, wherein the first region forms a side surface of an imaginary conical table having the central axis as the central axis. The identification device according to claim 1 or 2 , wherein the first region of the translucent member is light-diffused. The identification device according to claim 1 or 2 , wherein a light diffusing member is attached to the first region of the translucent member. The identification device according to claim 1 or 2 , wherein a light diffusing film is applied to the first region of the translucent member. The identification device according to any one of claims 1 to 5 , wherein the translucent member is made of resin. The identification device according to any one of claims 1 to 6 , wherein the identification object is a coin or a medal.

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