JP6642449B2 - Luminescent medium and inspection method thereof - Google Patents

Description

  The present invention relates to a light-emitting medium that emits light in a visible light wavelength region by wavelength conversion of light, and a method for inspecting the same.

  When irradiated with light in a certain wavelength range, electrons are excited, and when the electrons return to their original ground state, they emit light in accordance with the energy of the electrons. Materials having a wavelength conversion function of emitting light in a region are known. A representative example of such a material is a phosphor that converts ultraviolet light into visible light.

  Patent Literature 1 discloses that a pattern or the like made of a phosphor is formed on a cashable printed matter such as a banknote or a securities certificate or an identification card such as an ID certificate or a passport, and light from a light source such as a copying machine is used. When illuminated, hidden characters and images emerge to prevent forgery of the printed matter.

JP 2005-88546 A

  When a pattern or the like by the above-described phosphor is formed on a printed material such as a banknote, if a pattern or the like emerges in advance in which wavelength band, a copier that does not use a light source in the same wavelength band is used. There is a risk that the printed matter may be illegally copied.

  In addition, the above-described phosphor can be used for the purpose of storing secret information because information such as specific characters is not visually recognized unless specific light is irradiated. However, as described above, it is not so difficult to grasp in which wavelength band the light should be irradiated to reveal information. For example, if the wavelength of light applied to a printed material is continuously changed, the wavelength at which information is visually recognized can be easily detected.

As described above, in the related art, even if a phosphor is used for storing secret information, it cannot be said that the confidentiality is high.
Patent Literature 1 uses a material that converts the wavelength of light from a light source into a wavelength in a visible light band so that information can be visually recognized. However, if information is recorded using a material that emits light in a wavelength band that cannot be seen visually, and information is automatically grasped using a device that senses this light, the information will not be seen, so it will be confidential. Therefore, since the authenticity of the information can be automatically determined, the speed and accuracy of the determination process can be secured.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a light emitting medium capable of more reliably preventing forgery, preventing duplication, and improving confidentiality, and a method for inspecting the same. It is.

In order to solve the above problems, in one embodiment of the present invention, a substrate,
A first light emitter that is disposed on the base material and emits light in the visible light wavelength range when irradiated with light in the first wavelength range longer than the visible light wavelength range,
A second light emitter disposed on the base material and emitting light in the visible light wavelength range when irradiated with light in the second wavelength range shorter than the visible light wavelength range.

  The emission color when the first light emitting body is irradiated with the light in the first wavelength range may be a similar color to the light emission color when the second light emitting body is irradiated with the light in the second wavelength range. .

  The first light emitter and the second light emitter may be arranged so as not to overlap on the base material.

  The first light emitter and the second light emitter are visible when the second light emitter is irradiated with light in the second wavelength range while the first light emitter is irradiated with light in the first wavelength range. It may include at least one information of a specific pattern, picture, character, symbol, and numeral that can be used.

The first luminous body may be a first coating material that emits light in a visible light wavelength range when irradiated with light in the first wavelength range,
The second luminous body may be a second coating material that emits light in a visible light wavelength range when irradiated with light in the second wavelength range,
The first application material and the second application material may be applied on the base material according to the outline of the information.

In another embodiment of the present invention, a substrate,
A first illuminator that is disposed on the base material and emits light in a second wavelength range when irradiated with light in a first wavelength range;
A second light emitter that is disposed on the base material and emits light in the second wavelength range when irradiated with light in a third wavelength range different from the first wavelength range,
The first wavelength range is a wavelength range shorter than the visible light wavelength range,
The second wavelength range is an infrared wavelength range,
A light emitting medium is provided in which the third wavelength range is shorter or longer than the visible light wavelength range.

  The first wavelength range may be an ultraviolet light wavelength range.

  The third wavelength range may be an ultraviolet wavelength range or an infrared wavelength range.

The first light emitter emits light in the second wavelength range having a longer wavelength than the first wavelength range,
The second light emitter may emit light in the second wavelength range having a shorter wavelength than the third wavelength range.

The first light emitter emits light in the second wavelength range having a longer wavelength than the first wavelength range,
The second light emitter may emit light in the second wavelength range having a longer wavelength than the third wavelength range.

In another aspect of the present invention, a first luminous body that is disposed on a base material and emits light in a second wavelength range when irradiated with light in a first wavelength range, A second luminous body that emits light in the second wavelength range when irradiated with light in a third wavelength range different from the one wavelength range. Irradiating the second luminous body with the light of the third wavelength range while irradiating the body with the light of the first wavelength range;
While irradiating the first luminous body on the base material with the light of the first wavelength range, the second luminous body is irradiated with the light of the third wavelength range, the first luminous body and the Inspecting the surface of the second illuminant.

The first wavelength range is a wavelength range longer than a visible light wavelength range,
The second wavelength range is a visible light wavelength range,
The third wavelength range may be shorter than the visible light wavelength range.

The first wavelength range is a wavelength range shorter than the visible light wavelength range,
The second wavelength range is an infrared wavelength range,
The third wavelength range may be shorter or longer than the visible light wavelength range.

  According to the present invention, forgery prevention, copy prevention, and confidentiality can be more reliably improved.

FIG. 2 is a longitudinal sectional view of the light emitting medium 1. FIG. 2 is a plan view of the light emitting medium 1. The figure which shows an example which specifies the location of the 1st light emitting body 3 and the 2nd light emitting body 4. The figure which shows the other example which specifies the location of the 1st light emitting body 3 and the 2nd light emitting body 4. The figure which shows an example of the information represented by the 1st light emitting body 3 and the 2nd light emitting body 4. FIG. The figure which shows another example of the information represented by the 1st light emitting body 3 and the 2nd light emitting body 4. FIG. FIG. 1 is a diagram showing a schematic configuration of a luminous medium inspection device 10 according to an embodiment of the present invention. FIG. 7 is a diagram illustrating light wavelength conversion according to the second embodiment.

  Hereinafter, embodiments of the present invention will be described in detail. In the drawings attached to the present specification, the scale, the length-to-width dimension ratio, and the like are appropriately changed or exaggerated from those of the actual product for convenience of illustration and understanding.

(First embodiment)
FIG. 1A is a longitudinal sectional view of the light emitting medium 1, and shows a sectional structure taken along the line AA of the plan view shown in FIG. 1B. As shown in FIGS. 1A and 1B, the luminous medium 1 includes a first luminous body 3 and a second luminous body 4 disposed on a base material 2.

  The base material 2 may be a material having excellent adhesion to the first light emitting body 3 and the second light emitting body 4, and a specific material is not particularly limited. For example, a transparent or opaque resin material, an inorganic material such as glass, or a fiber material such as paper may be used.

  The first light emitter 3 and the second light emitter 4 are visible when the first light emitter 3 is irradiated with light in the first wavelength range and the second light emitter 4 is irradiated with light in the second wavelength range. The information includes at least one information of a specific pattern, picture, character, symbol, and numeral.

  More specifically, the first light emitter 3 emits light in the visible light wavelength range when irradiated with light in the first wavelength range longer than the visible light wavelength range. As described above, the first light emitting body 3 is an up-conversion type light emitting body that converts light having a long wavelength into visible light having a short wavelength.

  In addition, the second light emitter 4 emits light in the visible light wavelength range when irradiated with light in the second wavelength range shorter than the visible light wavelength range. As described above, the second light emitting body 4 is a fluorescent light emitting body that converts light having a short wavelength into visible light having a long wavelength.

  The first wavelength range is, for example, a wavelength longer than 0.8 μm, and is typically an infrared wavelength range (0.8 μm to 1 mm). Since the first light emitter 3 only needs to be able to emit light in the visible light wavelength range, the first wavelength range may be a wavelength range longer than the infrared wavelength range (for example, a terahertz wave or a millimeter wave).

  The second wavelength range is, for example, a wavelength shorter than 0.4 μm, and is typically a wavelength range of ultraviolet rays (0.01 μm to 0.4 μm). Since the second light emitter 4 only needs to be able to emit light in the visible light wavelength range, the second wavelength range may be a wavelength range shorter than the ultraviolet wavelength range (for example, X-rays).

  The visible light wavelength range in which the first light emitter 3 and the second light emitter 4 emit light is, for example, 0.4 μm to 0.8 μm.

  The emission color in the visible light wavelength range emitted by the first light emitter 3 and the emission color in the visible light wavelength range emitted by the second light emitter 4 may be any color that can be visually recognized by human eyes. In this case, it is not particularly intended that the emission color of the visible light wavelength range emitted by the first light emitter 3 and the emission color of the visible light wavelength range emitted by the second light emitter 4 can be distinguished. Therefore, the emission color in the visible light wavelength range emitted by the first light emitter 3 and the emission color in the visible light wavelength range emitted by the second light emitter 4 are preferably similar colors. Here, the similar color refers to, for example, that the emission color of the second light-emitting body 4 is within 1/6 of the emission color of the first light-emitting body 3 in the hue circle.

  Note that the emission color of the visible light wavelength range emitted by the first light emitter 3 and the emission color of the visible light wavelength range emitted by the second light emitter 4 do not need to be the same color. That is, the luminescent color of the first luminous body 3 and the luminescent color of the second luminous body 4 may be different from each other to such an extent that the color difference can be identified by human eyes.

  In the first light emitting body 3, when the light in the first wavelength range is irradiated, the electrons in the first light emitting body 3 are excited, and when the excited electrons return to the ground state, extra energy is emitted as visible light. . Specific examples of the material of the first light emitter 3 include erbium (Er), holmium (Ho), praseodymium (Pr), thulium (Tm), neodymium (Nd), gadolinium (Gd), europium (Eu), It contains at least one or more rare earth elements selected from the group consisting of samarium (Sm), terbium (Tb), dysprosium (Dy), and cerium (Ce), and the base material of the phosphor particles is a halide. Can be

  In the second luminous body 4, the electrons in the second luminous body 4 are excited when irradiated with light in the second wavelength range, and extra energy is emitted as visible light when the excited electrons return to the ground state. . Specific materials of the second luminous body 4 include, for example, fluorescein-based fluorescent dyes, coumarin-based fluorescent dyes, and rhodamine-based fluorescent dyes as dyes, and europium / manganese-activated barium magnesium aluminate as inorganic pigments. Manganese-activated zinc silicate, europium-activated yttrium oxide, europium-activated yttrium sulfide, zinc oxide, manganese-activated zinc germanate, europium-activated yttrium phosphorus vanadate, and the like.

  Some luminous bodies emit light when irradiating light in a certain wavelength range and continue to emit light for a while, even if the irradiation of light is stopped, so-called phosphorescence, In the present embodiment, it is desirable to select a material that emits light only during irradiation with light in a predetermined wavelength range. The reason for this is that, as will be described later, the light emission according to the present embodiment is performed for the purpose of obtaining secret information recorded on the light emitting medium 1 only when light in two wavelength ranges is simultaneously irradiated. This is because the medium 1 can be used.

  The first illuminant 3 is a first coating material (for example, ink) that emits light in a visible light wavelength range when irradiated with light in the first wavelength range. The second luminous body 4 is a second coating material (for example, ink) that emits light in the visible light wavelength range when irradiated with light in the second wavelength range. The first coating material and the second coating material are applied on the base material 2 according to the outline of the information.

  The first luminous body 3 and the second luminous body 4 are, for example, colorless or nearly colorless materials, and it is not possible to visually recognize where the first luminous body 3 and the second luminous body 4 are arranged on the luminous medium 1. There is a risk. Therefore, the first luminous body 3 and the second luminous body 4 may be colored with a predetermined pigment. However, it is necessary to prevent the contents of the information represented by the first luminous body 3 and the second luminous body 4 from being specified by the color of the pigment. For example, as shown in FIG. 2A, instead of mixing the pigment into the first luminous body 3 and the second luminous body 4, the first luminous body 3 and the second luminous body 4 are formed on the base material 2 in accordance with the formation range of the second luminous body 4. May be coated with a pigment. FIG. 2A is colored in each color by making the color on the base material 2 indicating the formation range 5a of the first light emitting body 3 and the color on the base material 2 indicating the formation range 5b of the second light emitting body 4 different. It is possible to grasp that it is necessary to make the wavelengths of the light to be applied to the regions 5a and 5b different from each other.

  Alternatively, as shown in FIG. 2B, frames 6a and 6b indicating the positions where the first luminous body 3 and the second luminous body 4 are arranged are printed on the base material 2, and the first and second colorless transparent bodies are provided inside the frames 6a and 6b. The luminous body 3 and the second luminous body 4 may be arranged. In this case, the presence of the colorless and transparent first light-emitting body 3 and the second light-emitting body 4 cannot be visually recognized, but by providing the frames 6a and 6b on the base material 2, the first light-emitting body is provided inside the frames 6a and 6b. It can be easily recognized that the body 3 and the second light emitting body 4 are arranged. In FIG. 2B, it is necessary to change the wavelength of the light to be irradiated by setting the frame line 6a surrounding the formation range of the first light emitting body 3 to be a solid line and the frame line 6b surrounding the formation range of the second light emitting body 4 to be a broken line. I am trying to understand that there is something.

  When the entire surface of the light emitting medium 1 is irradiated with the light for the first light emitter 3 and the light for the second light emitter 4, these lights are also applied to the first light emitter 3 and the second light emitter 4. Since the irradiation is performed, even if both the first light emitting body 3 and the second light emitting body 4 are colorless and transparent, the first light emitting body 3 and the second light emitting body 4 can emit light without any trouble. Therefore, it is not essential to mix and color the first luminous body 3 and the second luminous body 4 with a pigment.

  However, when the entire surface of the light emitting medium 1 is irradiated with the light for the first light emitting body 3 and the light for the second light emitting body 4, the light for the first light emitting body 3 causes the second light emitting body 4 to emit light. In contrast, the frequency range in which each of the first luminous body 3 and the second luminous body 4 emits light should be set as small as possible so that the first luminous body 3 does not emit light due to the light for the second luminous body 4. It is necessary to make it narrow so that the frequency ranges do not overlap.

  FIGS. 3A and 3B show information visually recognized when the first light emitting body 3 is irradiated with light in the first wavelength range and information visually recognized when the second light emitting body 4 is irradiated with light in the second wavelength range. It is a figure showing an example of.

  As shown in these drawings, the first light emitter 3 and the second light emitter 4 are arranged at different locations on the base material 2. There are two main reasons for arranging them in different places. The first reason is that when the first light emitting body 3 and the second light emitting body 4 are arranged in the same place on the base material 2, the light in one of the first wavelength band and the second wavelength band is emitted. This is because it becomes difficult to specify which of the first luminous body 3 and the second luminous body 4 is information that is visually recognized when the light is irradiated. The second reason is that when the light in both the first wavelength range and the second wavelength range is simultaneously irradiated, the information of the first light emitter 3 and the information of the second light emitter 4 are different. This is because information is superimposed and visually recognized, and information cannot be separated and extracted in the superimposed region. When the line of the first light emitter 3 and the line of the second light emitter 4 intersect, or when at least a part of the first light emitter 3 and the second light emitter 4 contact each other, the first light emitter 3 When the and the second luminous body 4 are visually recognized in a similar color, it is difficult to know which luminous body line or area. Therefore, it is desirable that the first light-emitting body 3 and the second light-emitting body 4 be arranged with a certain distance therebetween.

  In the example of FIGS. 3A and 3B, the first luminous body 3 and the second luminous body 4 having the same size and the same rectangular shape are arranged adjacent to each other, but the sizes of the first luminous body 3 and the second luminous body 4 are different. The shape is not particularly limited. Further, in FIG. 3A, while the plurality of first light emitters 3 are dispersed and arranged, the plurality of second light emitters 4 are also dispersed, but the first light emitter 3 and the second light emitter 4 are not arranged. There is no particular limitation on the number or arrangement. For example, as shown in FIG. 3B, the plurality of first light emitters 3 may be collectively arranged in one region, and the plurality of second light emitters 4 may be arranged collectively in another region.

  In FIG. 3A and FIG. 3B, one piece of meaningful information is completed only by combining information visually recognized by light emission by the first light emitter 3 and information visually recognized by light emission by the second light emitter 4. Like that. For example, in the case of FIG. 3A, the character “A” is visually recognized by combining the information visually recognized by the light emission of the first light emitter 3 and the information visually recognized by the light emission of the second light emitter 4. Like that. In the case of FIG. 3B, the information visually recognized by the light emission of the first light emitter 3 and the information visually recognized by the light emission of the second light emitter 4 are combined so that the picture representing the house is visually recognized. I have to.

  As described above, the light emitting medium 1 according to the present embodiment has a meaning only when the first light emitting body 3 is irradiated with light in the first wavelength range and the second light emitting body 4 is irradiated with light in the second wavelength range. Make certain information visible. Thereby, while irradiating the first luminous body 3 with the light of the first wavelength range and not irradiating the second luminous body 4 with the light of the second wavelength range, meaningful information can be transmitted from the luminous medium 1. It cannot be obtained, and the confidentiality of information can be improved.

  Although it is possible that the emission wavelength may be specified by continuously changing the emission wavelength of the irradiation light, in the present embodiment, the first light emitter 3 and the second light emitter 4 emit light in separate wavelength ranges. Therefore, the possibility of acquiring information by irradiating the first light emitter 3 and the second light emitter 4 with light in wavelength ranges corresponding to the respective light sources at the same timing is extremely low.

  In addition, even if an attempt is made to duplicate the light emitting medium 1 according to the present embodiment, the first light emitting body 3 cannot be seen unless the light in the first wavelength range is irradiated, and the second light emitting body 4 does not emit light in the second wavelength range. Since the light emitting wavelength range of the first light emitting body 3 and the light emitting wavelength range of the second light emitting body 4 are both less noticeable, the risk of being duplicated is also reduced.

  Furthermore, when the luminous medium 1 according to the present embodiment is used for authenticity determination, when the first luminous body 3 is irradiated with light of the first wavelength range while the second luminous body 4 is irradiated with light of the second wavelength range. Since it is sufficient to check whether or not the originally intended meaningful information can be visually recognized, the authenticity can be determined only by the first luminous body 3 and the second luminous body 4, and the authenticity determination process is performed. Can be simplified, and the authenticity can be easily determined visually by a human.

  FIG. 4 is a diagram showing a schematic configuration of the luminous medium inspection device 10 according to one embodiment of the present invention. The light emitting medium inspection device 10 of FIG. 4 includes an infrared light irradiating unit 11 that irradiates the above-described light emitting medium 1 with infrared light, an ultraviolet light irradiating unit 12 that irradiates the light emitting medium 1 with ultraviolet light, An imaging unit 13 for imaging the front surface and a display unit 14 for displaying a captured image are provided.

  The infrared light irradiating unit 11 irradiates the first luminous body 3 on the light emitting medium 1 with light in a first wavelength range (for example, an infrared wavelength range), and the ultraviolet light irradiating unit 12 emits second light on the light emitting medium 1. The body 4 is irradiated with light in a second wavelength range (for example, an ultraviolet wavelength range).

  As described above, the present embodiment considers that the first light emitter 3 is irradiated with light in the first wavelength range while the second light emitter 4 is irradiated with light in the second wavelength range. That is, the timing at which the infrared light irradiator 11 irradiates the first light emitter 3 with light is the same as the timing at which the ultraviolet light irradiator 12 irradiates light to the second light emitter 4.

  For example, when the beam diameter of the light emitted from the infrared light irradiating unit 11 is smaller than the surface area of the first light emitting unit 3, the light irradiated from the infrared light irradiating unit 11 is irradiated on the first light emitting unit 3. The scanning may be performed at a high speed to make it appear to the human eyes that the entire surface of the first light emitting body 3 is irradiated at the same timing. The same applies to the ultraviolet light irradiation unit 12.

  When the first luminous body 3 and the second luminous body 4 are distinguished from each other by a color such as a pigment, the light is irradiated from the infrared light irradiating unit 11 in accordance with the position of the first luminous body 3 and It is desirable to irradiate light from the ultraviolet light irradiating unit 12 in accordance with the position of the second light emitting body 4. In this case, first, the entire surface of the luminous medium 1 is imaged, the positions of the first luminous body 3 and the second luminous body 4 are automatically detected, and the positions of the first luminous body 3 and the second luminous body 4 are adjusted. The irradiation direction of the light from the ultraviolet light irradiation unit 12 may be automatically switched.

  Further, as described above, when the first light emitting body 3 and the second light emitting body 4 are colorless and transparent and the positions of the first light emitting body 3 and the second light emitting body 4 cannot be specified in appearance, the infrared light irradiating unit is used. The light from the ultraviolet light irradiator 11 and the ultraviolet light irradiator 12 may be applied to the entire surface of the light emitting medium 1. In this case, when the beam diameter of the light from the infrared light irradiation unit 11 and the ultraviolet light irradiation unit 12 is smaller than the surface area on the light emitting medium 1, the light from the infrared light irradiation unit 11 and the ultraviolet light irradiation unit 12 May be scanned on the light emitting medium 1 at high speed. Alternatively, an optical system is provided on the optical axis rear side of the infrared light irradiating unit 11 and the ultraviolet light irradiating unit 12, and the beam diameter of the light from each irradiating unit is widened to irradiate the entire surface of the light emitting medium 1. Is also good.

  The display unit 14 shown in FIG. 4 is a state in which the infrared light irradiating unit 11 irradiates the first luminous body 3 with light and the ultraviolet light irradiating unit 12 irradiates the second luminous body 4 with light. 1 is imaged and displayed on the entire surface.

  The luminous medium inspection device 10 of FIG. 4 is used for at least one of an inspection as to whether the luminous medium 1 is authentic, a detection of specific information embedded in the luminous medium 1, and a duplication prevention of the luminous medium 1. be able to.

  For example, in the surface image on the light emitting medium 1 displayed on the display unit 14 in FIG. 4, if the information originally intended is visually recognized by both the first light emitting body 3 and the second light emitting body 4, the light emitting medium 1 Can be determined to be authentic. This information becomes visible only when the first light emitter 3 is irradiated with light in the first wavelength range and the second light emitter 4 is irradiated with light in the second wavelength range. Even if the information is recorded on the medium 1, the possibility that the information is read without permission is reduced.

  In addition, since it is difficult for a third party to easily recognize information when the first luminous body 3 and the second luminous body 4 are each irradiated with light in a specific wavelength range, the luminous medium according to the present embodiment is used. 1 is less likely to be duplicated.

  As described above, in the present embodiment, the first luminous body 3 that emits light in the visible wavelength range when irradiated with light in the first wavelength range and the visible light wavelength range when irradiated with light in the second wavelength range. Since the second light-emitting body 4 that emits light in the band is disposed on the light-emitting medium 1, the first light-emitting body 3 and the second light-emitting body 4 are irradiated with light in the wavelength ranges respectively corresponding to the first light-emitting body 3 and the second light-emitting body 4. The body 3 and the second light-emitting body 4 emit light together, and specific information can be visually recognized. Since this information cannot be seen unless the first light emitting body 3 and the second light emitting body 4 are irradiated with light in the corresponding wavelength ranges, secret information that cannot be easily read is recorded on the light emitting medium 1. be able to. Thereby, it is possible to perform an inspection as to whether the light emitting medium 1 is authentic, use the light emitting medium 1 as a storage location for secret information, and prevent the light emitting medium 1 from being duplicated.

(Second embodiment)
In the above-described first embodiment, an example in which the first light emitting body 3 and the second light emitting body 4 emit light in a visible light wavelength range has been described. The body 3 and the second luminous body 4 emit light in the infrared wavelength range.

  The cross-sectional structure of the luminescent medium according to the second embodiment is the same as that in FIGS. 1A and 1B. The first light emitter 3 according to the second embodiment emits light in the second wavelength range when irradiated with light in the first wavelength range. The second luminous body 4 emits light in the second wavelength range when irradiated with light in the third wavelength range different from the first wavelength range.

  The first wavelength range is a wavelength range shorter than the visible light wavelength range. As a more specific example, the first wavelength range is an ultraviolet light wavelength range or an infrared light wavelength range.

  The second wavelength range is an infrared light wavelength range. The third wavelength range is a wavelength range shorter or longer than the visible light wavelength range. More specifically, the third wavelength range is an infrared light wavelength range.

  FIG. 5 is a diagram illustrating light wavelength conversion according to the second embodiment. That is, FIGS. 5A and 5B are diagrams schematically showing the wavelength conversion of light of the first light emitter 3 and the second light emitter 4. The first light emitter 3 and the second light emitter 4 may perform wavelength conversion as shown in FIG. 5A or may perform wavelength conversion as shown in FIG. 5B.

  In the example of FIG. 5A, the first light emitter 3 performs down-conversion by irradiating light in the ultraviolet light wavelength range and emitting light in the infrared light wavelength range. Further, the second light emitting body 4 performs up-conversion by irradiating light in the infrared light wavelength range and emitting light in the infrared light wavelength range shorter than the light.

  In the example of FIG. 5B, the first light emitter 3 performs down-conversion by irradiating light in the ultraviolet light wavelength range and emitting light in the infrared light wavelength range. Further, the second light emitting body 4 performs down-conversion by irradiating light in the infrared light wavelength range and emitting light in the infrared light wavelength range longer than that light.

A material that emits light in the infrared wavelength range by irradiating light in the ultraviolet wavelength range and a material that emits light in another infrared wavelength range by irradiating light in the infrared wavelength range The specific type is not particularly limited. For example, an inorganic phosphor such as YVO ₄ : Nd or Y ₂ O ₂ S: Nd can be applied as a specific material that emits light in the infrared wavelength range by irradiating light in the ultraviolet wavelength range. is there. Alternatively, an organic light conversion material such as nanodiamond may be applied. Alternatively, phosphor fine particles having a perovskite structure represented by BaSnO ₃ may be applied. Alternatively, a rare earth metal such as Eu or Ce may be used.

  The first light emitter 3 and the second light emitter 4 according to the second embodiment emit light in the infrared wavelength range when irradiated with light in the ultraviolet wavelength range or the infrared wavelength range. The light cannot be recognized visually. Therefore, a dedicated device for detecting the light emitted from the first light emitter 3 and the second light emitter 4 is required. The light emitting medium inspection device 10 incorporating such a dedicated device can be configured similarly to FIG. In the case of the first embodiment, the imaging unit 13 in the luminous medium inspection device 10 of FIG. 4 detects visible light, whereas the imaging unit 13 of the second embodiment uses infrared light. Is to be detected. More specifically, the imaging unit 13 according to the second embodiment detects infrared light emitted from the light emitting medium 1 and converts the infrared light into an image signal. This image signal is displayed on the display unit 14.

  As described above, in the second embodiment, when light in the ultraviolet wavelength range is irradiated, light in the infrared wavelength range is emitted, or when light in the infrared wavelength range is irradiated, the wavelength range is shifted. It emits light in the infrared wavelength range. Visually, it is not possible to determine whether the light is shining in the desired wavelength range or not, and it is possible to determine for the first time using a dedicated device, so that the security performance is improved. Therefore, the light emitting medium of the present embodiment is suitable for applications where security is important, such as forgery prevention. Further, by applying the luminous medium of the present embodiment to the luminous medium inspection device 10 of FIG. 4, it is possible to determine whether the luminous wavelength range is regular or not more accurately and quickly than relying on visual observation.

  The aspects of the present invention are not limited to the individual embodiments described above, but include various modifications that can be conceived by those skilled in the art, and the effects of the present invention are not limited to the contents described above. That is, various additions, changes, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

    REFERENCE SIGNS LIST 1 light emitting medium, 2 base material, 3 first light emitting body, 4 second light emitting body, 10 light emitting medium inspection device, 11 infrared light irradiation section, 12 ultraviolet light irradiation section, 13 imaging section, 14 display section

Claims (13)

A substrate,
A first luminous body that is arranged on the base material and emits light in a second wavelength range when irradiated with light in a first wavelength range;
A second luminous body that is arranged on the base material and emits light in the second wavelength range when irradiated with light in a third wavelength range different from the first wavelength range;
A first application region provided in a region including the arrangement region of the first luminous body on the base material and coated with a first pigment having visible light visibility;
A second application region provided in a region including the arrangement region of the second luminous body on the base material and coated with a second pigment having visible light visibility. A substrate,
A first luminous body that is arranged on the base material and emits light in a second wavelength range when irradiated with light in a first wavelength range;
A second luminous body that is arranged on the base material and emits light in the second wavelength range when irradiated with light in a third wavelength range different from the first wavelength range;
A first frame with visible light visibility, representing an outer frame of a region including the arrangement region of the first light emitter on the base material;
And a second frame having visible light visibility and a different display form from the first frame, the second frame representing an outer frame of a region including the arrangement region of the second light emitter on the base material. The first luminous body emits light in the visible wavelength region when irradiated with light of longer the first wavelength range than the visible light wavelength region,
Said second light emitter, the light emitting medium according to claim 1 or 2 for emitting light in the visible wavelength region when irradiated with light of shorter the third wavelength range than the visible light wavelength region. 4. A color emitted when the first light emitter is irradiated with light in the first wavelength range is a color similar to the light emitted when the second light emitter is irradiated with light in the third wavelength range. The luminescent medium according to item 1.   The luminous medium according to claim 1, wherein the first luminous body and the second luminous body are separately arranged on the base material. The first illuminant and the second illuminant are visible when illuminating the first illuminant with light in the first wavelength range and irradiating the second illuminant with light in the third wavelength range. The luminescent medium according to any one of claims 1 to 5, wherein the luminescent medium includes at least one information of a specific pattern, pattern, character, symbol, and numeral that can be used. The first luminous body is a first coating material that emits light in a visible light wavelength range when irradiated with light in the first wavelength range,
The second luminous body is a second coating material that emits light in a visible light wavelength range when irradiated with light in the third wavelength range,
The luminescent medium according to claim 6, wherein the first coating material and the second coating material are applied on the base material in accordance with the outline of the information. The first light emitter emits light in a second wavelength range when irradiated with light in a first wavelength range,
The second light emitter emits light in the second wavelength range when irradiated with light in a third wavelength range different from the first wavelength range,
The first wavelength range is a wavelength range shorter than the visible light wavelength range,
The second wavelength range is an infrared wavelength range,
The luminescent medium according to claim 1, wherein the third wavelength range is a wavelength range shorter or longer than a visible light wavelength range. The first light emitter emits light in the second wavelength range having a longer wavelength than the first wavelength range,
The luminous medium according to claim 8, wherein the second luminous body emits light in the second wavelength range having a shorter wavelength than the third wavelength range. The first light emitter emits light in the second wavelength range having a longer wavelength than the first wavelength range,
The luminous medium according to claim 8, wherein the second luminous body emits light in the second wavelength range having a longer wavelength than the third wavelength range. A first illuminant that is disposed on the base material and emits light of the second wavelength range when irradiated with light of the first wavelength range; and a third wavelength that is disposed on the base material and is different from the first wavelength range. A second light-emitting body that emits light in the second wavelength range when irradiated with light in a region, and a visible light visibility provided in a region including an arrangement region of the first light-emitting member on the base material. A first frame having visible light visibility, which represents an outer frame of a first coating region coated with a certain first pigment, or a region including an arrangement region of the first luminous body on the substrate, and A second coating area provided with a second pigment having visible light visibility provided in an area including the arrangement area of the second light emitter, or an arrangement area of the second light emitter on the base material. A second frame having a visible light visibility that represents an outer frame of the included region and having a different display form from the first frame. A step of to irradiation, while irradiating the light of the first wavelength range to the first light emitter on the substrate, the third wavelength region light to the second light emitter,
While irradiating the first luminous body on the base material with the light of the first wavelength range, the second luminous body is irradiated with the light of the third wavelength range, the first luminous body and the Inspecting the surface of the second illuminant. The first wavelength range is a wavelength range longer than a visible light wavelength range,
The second wavelength range is a visible light wavelength range,
The method according to claim 11, wherein the third wavelength range is shorter than a visible light wavelength range. The first wavelength range is a wavelength range shorter than the visible light wavelength range,
The second wavelength range is an infrared wavelength range,
The method according to claim 11, wherein the third wavelength range is a wavelength range shorter or longer than a wavelength range of visible light.