Representation

Abstract

Provided is a display technique that enables special image display. A display body (1) comprises: a light-shielding layer (12) provided with a plurality of slits (SL) arranged at intervals in the width direction; and an image recording layer (22) that is opposed at an interval to one principal surface of the light-shielding layer (12), and in which a latent image that becomes visible by being partially shielded by the light-shielding layer (12) is recorded.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to display technology. [Background technology]

[0002] Identification (ID) cards, such as employee ID cards, driver's licenses, and student ID cards, contain fixed information, such as background patterns, as well as individual information, such as a name, a card-specific number, and an expiration date. These ID cards are used, for example, to identify individuals within a facility or upon entry and exit. To prevent counterfeiting or alteration, ID cards are specially printed with special ink and feature a photograph or hologram. Similar countermeasures are also used for payment cards, credit cards, automated teller machine (ATM) cards, and membership cards. Similar countermeasures are also used for data pages in passports and visas.

[0003] However, with the recent spread of color copying machines and the emergence of highly functional photolithography equipment, counterfeiting and alteration techniques have become more sophisticated, and the risk of crimes involving counterfeiting and alteration has increased.

[0004] Another method is to record invisible information on the ID card that cannot be discerned under normal conditions, and then use a reader or discriminator to determine whether the ID card is genuine. Because this invisible information cannot be discerned under normal conditions, this technology can be an even more effective anti-counterfeiting measure.

[0005] One way to visualize invisible information is to print a thin line or halftone dot pattern on the ID card in advance, and then overlay a discrimination film or lenticular that interferes with this pattern to create a moire pattern. The presence or absence and shape of this moire pattern can be used to determine the authenticity of the ID card. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 6-40190 [Patent Document 2] Japanese Patent Application Publication No. 2002-279480 [Patent Document 3] International Publication No. 2009 / 139396 Summary of the Invention

[0007] An object of the embodiment of the present invention is to provide a display technique that enables special image display.

[0008] According to one aspect of the present invention, there is provided a display comprising: a light-shielding layer having a plurality of slits arranged at intervals in the width direction of the slits; and a first image recording layer facing one main surface of the light-shielding layer at a distance and having a first latent image recorded thereon, the first latent image being visualized by being partially concealed by the light-shielding layer. The width direction of the slits is the direction in which the slits are repeated. Alternatively, the slits may be formed as a grid, and the width direction of the slits may be the vertical direction of the first latent image. This allows the latent image to be changed by a natural action of tilting the display in the vertical direction while observing the first latent image.

[0009] When this display is placed on a first surface having reflectance characteristics different from that of the light-shielding layer, with the light-shielding layer positioned between the first surface and the first image recording layer, and illuminated with white light from the first image recording layer side, and the reflected light is observed under these conditions (hereinafter, this observation condition is referred to as the first observation condition), the light-shielding layer can exhibit a concealing effect that partially conceals the first latent image. For example, if the first surface has a lower reflectance than the light-shielding layer, the portion of the first latent image corresponding to the slits can be concealed. Alternatively, if the first surface has a higher reflectance than the light-shielding layer, the portion of the first latent image corresponding to the slits can be unconcealed, and the remaining portion can be concealed. Therefore, in this case, the viewer can visually recognize a first visible image that is made visible by partially concealing the first latent image with the light-shielding layer.

[0010] Even when this display is illuminated with white light from the light-shielding layer side or the first image-recording layer side and the transmitted light is observed (hereinafter, this observation condition is referred to as the second observation condition), the light-shielding layer still exerts a concealing effect that partially conceals the first latent image, and therefore, in this case as well, the observer can visually recognize the first visible image.

[0011] When this display is placed on a second surface having a higher reflectivity than the light-shielding layer, with the first image recording layer positioned between the first surface and the light-shielding layer, and illuminated with white light from the light-shielding layer side, and the reflected light is observed in this state (hereinafter, this observation condition is referred to as the third observation condition), the light-shielding layer can exert a concealing effect that partially conceals the first latent image. That is, the portion of the first latent image corresponding to the slit is not concealed, and the remaining portion can be concealed. Therefore, in this case as well, the observer can visually recognize the first visible image.

[0012] Then, when this display is placed on a third surface having the same reflective properties as the light-shielding layer, with the light-shielding layer positioned between the second surface and the first image recording layer, and illuminated with white light from the first image recording layer side, and the reflected light is observed under this condition (hereinafter, this observation condition is referred to as the fourth observation condition), the light-shielding layer does not exert a concealing effect that partially conceals the first latent image, and the observer cannot see the first visible image.

[0013] Furthermore, since the first image recording layer faces one of the main surfaces of the light-shielding layer across a gap, the position of the portion of the first latent image that is concealed by the light-shielding layer changes when the observation angle is changed under any of the first to third observation conditions. Therefore, for example, the first visible image displayed by the display device under any of the first to third observation conditions can be changed depending on the observation angle.

[0014] In this way, the display can display various images depending on the viewing conditions, i.e., the display can display special images.

[0015] According to another aspect of the present invention, there is provided a display according to the above aspect, in which the distance from the light-shielding layer to the first image recording layer is within a range of 50 μm to 2 mm. If this distance is made shorter, the display becomes more prone to breaking. If this distance is made longer, the display becomes thicker. To achieve high printing accuracy with a general printing device, this distance is preferably within a range of 100 μm to 2 mm. It is more preferable that this distance be within a range of 150 μm to 1 mm, as this makes it easier to achieve higher printing accuracy.

[0016] Furthermore, if the distance is long, the position of the portion of the first latent image that is concealed by the light-shielding layer changes significantly when the observation angle is changed under any of the first to third observation conditions. Therefore, for example, the first visible image displayed by the display under any of the first to third observation conditions can be significantly changed depending on the observation angle. However, if the distance is excessively long, the viewer will perceive image flickering. To achieve a significant change in the image depending on the observation angle without causing the viewer to perceive image flickering, the distance is preferably within the range of 100 μm to 800 μm.

[0017] According to yet another aspect of the present invention, there is provided a display device according to any of the above aspects, wherein the first visible image, which is made visible by partially concealing the first latent image with the light-shielding layer, changes at least one of its color and shape by tilting the display device around an axis parallel to the longitudinal direction of the plurality of slits.

[0018] When the tilt angle of the display body is changed under any of the first to third viewing conditions, the position of the portion of the first latent image that is hidden by the light-shielding layer changes. Therefore, for example, the first image recording layer can be configured so that when the tilt angle is a first angle under any of the first to third viewing conditions, the display body displays a first image as the first visible image, and when the tilt angle is a second angle different from the first angle under that viewing condition, the display body displays a second image different from the first image as the first visible image. Therefore, even more unique image displays are possible.

[0019] According to yet another aspect of the present invention, there is provided the display device according to any one of the above aspects, wherein the first latent image is partially hidden by the light-shielding layer, thereby generating moire.

[0020] The first image recording layer may include periodically arranged patterns. For example, if these patterns are stripe patterns arranged in the width direction of the first latent image, and the length and width directions of these stripe patterns are equal to the length and width directions of the slits, respectively, and the period of the arrangement of these stripe patterns is different from the period of the slits, the first latent image may be partially hidden by the light-shielding layer, resulting in moire. Alternatively, if the arrangement direction of the stripe patterns is tilted relative to the arrangement direction of the slits, the first latent image may also be partially hidden by the light-shielding layer, resulting in moire.

[0021] According to yet another aspect of the present invention, there is provided a display element according to any of the above aspects, further comprising a transparent substrate between the light-shielding layer and the first image recording layer as a spacer for maintaining a distance between the light-shielding layer and the first image recording layer.

[0022] According to yet another aspect of the present invention, there is provided a display element according to any of the above aspects, further comprising a second image recording layer facing the other main surface of the light-shielding layer and having recorded thereon a second latent image that becomes visible when partially concealed by the light-shielding layer.

[0023] When this display is placed on a fourth surface having reflectance characteristics different from those of the light-shielding layer, with the second image-recording layer positioned between the fourth surface and the light-shielding layer, and illuminated with white light from the first image-recording layer side, and the reflected light is observed under this condition (hereinafter, this observation condition is referred to as the fifth observation condition), the light-shielding layer exhibits a concealing effect that at least partially conceals the first latent image. For example, when the fourth surface has a lower reflectance than the light-shielding layer, the second visible image, which is made visible by partially concealing the second latent image with the light-shielding layer, is darker than the first visible image, which is made visible by partially concealing the first latent image with the light-shielding layer. Therefore, the viewer can visually recognize the first visible image, which is made visible by partially concealing the first latent image with the light-shielding layer.

[0024] When this display is placed on the fourth surface with the first image recording layer positioned between the fourth surface and the light-shielding layer, illuminated with white light from the second image recording layer side, and the reflected light is observed under this condition (hereinafter, this observation condition is referred to as the sixth observation condition), the light-shielding layer exhibits a concealing effect that at least partially conceals the second latent image. For example, when the fourth surface has a lower reflectance than the light-shielding layer, the first visible image, which is made visible by partially concealing the first latent image with the light-shielding layer, is darker than the second visible image, which is made visible by partially concealing the second latent image with the light-shielding layer. Therefore, the observer can visually recognize the second visible image, which is made visible by partially concealing the second latent image with the light-shielding layer.

[0025] Even when this display is illuminated with white light from the first or second image recording layer side and the transmitted light is observed (hereinafter, this observation condition is referred to as the seventh observation condition), the light-shielding layer exhibits a concealing effect that partially conceals the first latent image and a concealing effect that partially conceals the second latent image. Therefore, in this case as well, the observer can visually recognize an image corresponding to the superposition of the first visible image and the second visible image.

[0026] When this display is placed on a fifth surface having the same reflection characteristics as the light-shielding layer, with the second image recording layer positioned between the fourth surface and the light-shielding layer, and illuminated with white light from the first image recording layer side, and the reflected light is observed under this condition (hereinafter, this observation condition is referred to as the eighth observation condition), the light-shielding layer exerts a concealing effect that partially conceals the second latent image. Therefore, if the reflectance of the light-shielding layer and the fifth surface is sufficiently high, the observer can visually recognize the superposition of the first latent image and the second visible image that is made visible by partially concealing the second latent image with the light-shielding layer.

[0027] When this display is placed on the fifth surface so that the first image recording layer is located between the fourth surface and the light-shielding layer, and illuminated with white light from the second image recording layer side, and the reflected light is observed under this condition (hereinafter, this observation condition is referred to as the ninth observation condition), the light-shielding layer exerts a concealing effect that partially conceals the first latent image. Therefore, if the reflectance of the light-shielding layer and the fifth surface is sufficiently high, the observer can visually recognize the superposition of the second latent image and the first visible image that is formed by partially concealing the first latent image with the light-shielding layer.

[0028] Furthermore, since the first image recording layer faces one of the main surfaces of the light-shielding layer across a gap, the position of the portion of the first latent image that is concealed by the light-shielding layer changes when the observation angle is changed under the fifth observation condition. Therefore, for example, the first visible image displayed by the display device under the fifth observation condition can be changed depending on the observation angle.

[0029] Furthermore, since the second image recording layer faces the other main surface of the light-shielding layer across a gap, the position of the portion of the second latent image that is concealed by the light-shielding layer changes when the observation angle is changed under the sixth observation condition. Therefore, for example, the second visible image displayed by the display device under the sixth observation condition can be changed depending on the observation angle.

[0030] In this way, the display can display various images depending on the viewing conditions, i.e., the display can also display special images.

[0031] According to yet another aspect of the present invention, there is provided a display device according to the above aspect, in which the second visible image, which is made visible by partially concealing the second latent image with the light-shielding layer, changes at least one of its color and shape by tilting the display device around an axis parallel to the longitudinal direction of the plurality of slits.

[0032] When the tilt angle of the display body is changed under the sixth observation condition, the position of the portion of the second latent image that is hidden by the light-shielding layer changes. Therefore, for example, the second image recording layer can be configured so that when the tilt angle is set to a third angle under the sixth observation condition, the display body displays a third image as the second visible image, and when the tilt angle is set to a fourth angle different from the third angle under that observation condition, the display body displays a fourth image different from the third image as the second visible image. Therefore, even more unique image displays are possible.

[0033] According to yet another aspect of the present invention, there is provided the display device according to any one of the above aspects, wherein the second latent image is partially hidden by the light-shielding layer, thereby generating moire.

[0034] The second image recording layer may include periodically arranged patterns. For example, if these patterns are stripe patterns arranged in the width direction, and the length and width directions of these stripe patterns are equal to the length and width directions of the slits, respectively, and the period of the arrangement of these stripe patterns is different from the period of the arrangement of the slits, the second latent image may be partially hidden by the light-shielding layer, resulting in moire. Alternatively, if the arrangement direction of the stripe patterns is tilted relative to the arrangement direction of the slits, the second latent image may also be partially hidden by the light-shielding layer, resulting in moire.

[0035] According to yet another aspect of the present invention, there is provided a display according to the above aspect, in which the distance from the light-shielding layer to the second image recording layer is within a range of 50 μm to 2 mm. If this distance is made shorter, the display becomes more prone to breaking. If this distance is made longer, the display becomes thicker. To achieve high printing accuracy with a general device, this distance is preferably within a range of 100 μm to 2 mm. It is more preferable that this distance be within a range of 150 μm to 1 mm, as this makes it easier to achieve higher printing accuracy.

[0036] Furthermore, if the distance is long, the position of the portion of the second latent image concealed by the light-shielding layer changes significantly when the observation angle is changed under the sixth observation condition. Therefore, for example, the second visible image displayed by the display device under the sixth observation condition can be significantly changed depending on the observation angle. However, if the distance is excessively long, the viewer will perceive image flickering. To increase the image change depending on the observation angle without causing the viewer to perceive image flickering, this distance is preferably within the range of 100 μm to 800 μm. It is preferable that the distance from the light-shielding layer to the second image-recording layer be equal to the distance from the light-shielding layer to the first image-recording layer.

[0037] According to yet another aspect of the present invention, there is provided a display element according to any of the above aspects, further comprising a first transparent substrate between the light-shielding layer and the first image recording layer as a spacer for maintaining a distance between the light-shielding layer and the first image recording layer, and further comprising a second transparent substrate between the light-shielding layer and the second image recording layer as a spacer for maintaining a distance between the light-shielding layer and the second image recording layer.

[0038] According to yet another aspect of the present invention, there is provided a display according to any one of the above aspects, wherein the pitch P1 of the plurality of slits is in the range of 50 to 500 μm. Considering the dimensions of the colored portion formed by printing or the like and the distance from the first main surface to the image display layer, the pitch P B A structure in which 1 is within the above range is suitable for changing an image under the second observation condition as described above. The pitch can be defined as the average distance between the centers of the slits. More specifically, it may be defined as the average distance between the centers of 10 slits.

[0039] The pitch P1 is preferably in the range of 100 to 350 μm. This configuration is advantageous for stable printing and is less likely to cause jagged edges in the image displayed on the display. The pitch P1 is more preferably in the range of 150 to 300 μm. This configuration achieves a particularly excellent appearance.

[0040] According to yet another aspect of the present invention, there is provided a display according to any of the above aspects, wherein a ratio W2 / P1 of a width W2 of the plurality of slits to a pitch P1 of the plurality of slits is in the range of 1 / 5 to 2 / 3, preferably in the range of 1 / 5 to 1 / 2, and more preferably in the range of 1 / 3 to 3 / 7.

[0041] A structure in which the ratio W2 / P1 is within the above range is suitable for displaying the first or second visible image brightly and for changing it as described above.

[0042] According to yet another aspect of the present invention, there is provided the display according to any one of the above aspects, wherein the light-shielding layer is a reflector.

[0043] According to yet another aspect of the present invention, there is provided the display according to any one of the above aspects, wherein the light-shielding layer is a metal vapor deposition layer.

[0044] When the light-shielding layer is a reflector, the reflector preferably includes a metal layer. The reflector may have a specular reflecting surface or a light-scattering surface.

[0045] Alternatively, according to yet another aspect of the present invention, there is provided a display according to any of the above aspects, wherein the light-shielding layer includes a colored pattern generated by laser beam drawing on a layer containing a thermosensitive color former, or includes a black pattern generated by carbonization through laser engraving. The light-shielding layer can also be a light absorber.

[0046] According to yet another aspect of the present invention, the display body according to any of the above aspects is provided on a part of a card. The display can also be placed on the data page of the booklet. [Brief explanation of the drawings]

[0047] [Figure 1] FIG. 1 is a plan view schematically showing a display according to a first embodiment of the present invention. [Figure 2] 2 is a cross-sectional view taken along line II-II of the display shown in FIG. 1. [Figure 3] 3 is a cross-sectional view taken along line III-III of the display shown in FIG. 1. [Figure 4] FIG. 4 is a plan view schematically showing a mask layer of the display shown in FIGS. [Figure 5] FIG. 4 is a plan view schematically showing an image carrier of the display shown in FIGS. 1 to 3. [Figure 6] FIG. 10 is a diagram schematically illustrating an example of observation conditions. [Figure 7] 7 is a diagram showing an example of an image displayed on the display device shown in FIGS. 1 to 3 under the viewing conditions of FIG. 6. FIG. [Figure 8] FIG. 10 is a diagram schematically showing another example of observation conditions. [Figure 9] 9 is a diagram showing an example of an image displayed on the display device shown in FIGS. 1 to 3 under the viewing conditions of FIG. 8; [Figure 10] FIG. 10 is a diagram schematically showing still another example of observation conditions. [Figure 11] FIG. 10 is a diagram schematically showing still another example of observation conditions. [Figure 12] FIG. 10 is a diagram schematically showing still another example of observation conditions. [Figure 13] FIG. 10 is a plan view schematically showing a mask layer of a display according to a modified example. [Figure 14] FIG. 10 is a plan view schematically showing an image recording layer of a display according to a modified example. [Figure 15] FIG. 10 is a plan view schematically showing a display according to a modified example. [Figure 16] FIG. 10 is a cross-sectional view schematically showing a display according to a second embodiment of the present invention. [Figure 17] FIG. 10 is a plan view schematically showing an application example of a display unit. [Figure 18] FIG. 10 is a plan view schematically showing another application example of the display unit. [Figure 19] FIG. 10 is a plan view schematically showing yet another application example of a display unit. [Figure 20] FIG. 10 is a plan view schematically showing yet another application example of a display unit. DETAILED DESCRIPTION OF THE INVENTION

[0048] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are more specific embodiments of any of the above aspects. Elements having the same or similar functions are designated by the same reference numerals, and redundant descriptions will be omitted.

[0049] <First embodiment of the present invention> Fig. 1 is a plan view schematically showing a display according to a first embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line II-II of the display shown in Fig. 1. Fig. 3 is a cross-sectional view taken along line III-III of the display shown in Fig. 1. Fig. 4 is a plan view schematically showing a mask layer of the display shown in Figs. 1 to 3. Fig. 5 is a plan view schematically showing an image carrier of the display shown in Figs. 1 to 3.

[0050] In each figure, the X direction is a direction parallel to the main surface of a light-shielding layer (described later), i.e., a direction parallel to the display surface of the display body. The Y direction is a direction parallel to the main surface and perpendicular to the X direction, i.e., a direction parallel to the display surface and perpendicular to the X direction. The Z direction is a direction perpendicular to the X and Y directions, i.e., a thickness direction of the display body.

[0051] The display member 1 shown in FIGS. 1 to 3 includes a mask layer 10, an image carrier 20, and an adhesive layer 30, as shown in FIGS.

[0052] As shown in FIGS. 2 to 4, the mask layer 10 includes a transparent substrate 11, a light-shielding layer 12, and a protective layer 13.

[0053] The transparent substrate 11 transmits part or all of light in the visible range and is preferably colorless and transparent.

[0054] The transparent substrate 11 can be a flexible substrate such as a sheet or film, or a rigid substrate such as a card. The transparent substrate 11 may be a single layer or a multilayer.

[0055] The material of the transparent substrate 11 can be an inorganic material such as glass, or a polymer, which can be a thermoplastic polymer or a curable compound. The thermoplastic polymer can be polycarbonate, acrylic polymer, fluorinated acrylic polymer, silicone, epoxy acrylate, polypropylene, polyethylene, polyester, polystyrene, cycloolefin polymer, methylstyrene polymer, fluorene polymer, polyethylene terephthalate (PET), polyacetal, and acrylonitrile-styrene copolymer. The curing compounds can be phenolic, melamine, urea, and alkyd resins.

[0056] As shown in FIGS. 2 to 4, the light-shielding layer 12 is provided on one main surface of the transparent substrate 11. The light-shielding layer 12 has a plurality of slits SL aligned at intervals in the width direction of the slits. That is, the slits are stripe-shaped. The slits also form a lattice. Here, the length direction of the slits SL is the X direction, and the width direction of the slits is the Y direction. In other words, the X axis is parallel to the length direction of the slits SL, and the Y axis is parallel to the width direction of the slits SL. That is, the X direction and the Y direction are perpendicular to each other. The X axis and the Y axis are perpendicular to each other and form a Cartesian coordinate system. The mask layer 10 is light-transmitting at the positions of the slits SL and light-shielding at other positions.

[0057] Each slit SL has a constant width W2 along the length direction. Adjacent slits SL have the same width W2. The slits SL are arranged at a constant pitch P1 in their width direction. In FIG. 4, the width W1 is the width of the portion of the light-shielding layer 12 sandwiched between adjacent slits SL. Here, as an example, the width W1 is assumed to be equal to the width W2.

[0058] A specific example of the light-shielding layer 12 is a light-shielding reflector. Another specific example of the light-shielding layer 12 is a light-absorbing material. The light-shielding layer 12 may be a layer in which a light-shielding reflector and a light-absorbing material are laminated, or may be a layer in which light-shielding reflectors and light-absorbing materials are arranged alternately.

[0059] The light-blocking reflector can be obtained by vacuum-depositing a metal layer and providing a slit SL therein. The material of the metal layer can be, for example, aluminum, chromium, nickel, iron, titanium, silver, gold, or copper, either alone or as an alloy. A metal oxide layer may also be provided on the surface. Vacuum deposition can be performed by vapor deposition or sputtering. The slit SL can also be formed by etching. Etching can be chemical etching or laser etching. Chemical etching can be a process in which the portions not to be etched are masked with resist to prevent etching, and the metal is dissolved with acid or alkali. Laser etching is also called laser engraving. Laser etching can be a process in which the portions of the metal layer irradiated with a laser beam are removed.

[0060] The light absorber can be formed by partial thermal transfer of an ink ribbon, ink jet printing, laser engraving, electrophotography, offset printing, screen printing, or a combination of two or more of these. Carbon black ink can be used for printing the light absorber.

[0061] The light absorber can be formed by laser engraving. The light absorber can also be formed by drawing with a laser beam on a layer containing a thermosensitive color former. The protective layer 13 can be a layer containing a thermosensitive color former. That is, the light absorber can be a light absorber drawn with a laser beam. The light absorber obtained in this manner includes a colored pattern generated by laser beam drawing. The light absorber can be a colored light absorber. That is, the light absorber can be a colored pattern. Alternatively, the light absorber may include a carbonized pattern generated by carbonization due to laser engraving. The light absorber can be a carbonized light absorber. That is, the light absorber can be a carbonized pattern. The carbonized pattern can be formed in the protective layer 13. Such a light absorber drawn with a laser beam can form an individual pattern. Furthermore, a light absorber drawn with a laser beam cannot be erased because the material is irreversibly altered. Therefore, it is difficult to tamper with. Here, as an example, the light-shielding layer 12 is made of metal and is a light-shielding reflector provided with slits SL.

[0062] The protective layer 13 is provided on the transparent substrate 11 and the light-shielding layer 12. The protective layer 13 protects the light-shielding layer 12 from damage. The protective layer 13 can also serve as a substrate for the light-shielding layer 12. When the light-shielding layer 12 is formed on the transparent substrate 11, the protective layer 13 can be omitted.

[0063] The protective layer 13 is transparent to light in the visible range, and is preferably colorless and transparent.

[0064] The protective layer 13 can be a sheet or a film. For example, the protective layer 13 can be a polymer sheet or a polymer film. The protective layer 13 can be a single layer or a multilayer. In the case of a multilayer, the protective layer 13 may have a hard coat layer on the transparent substrate side and an antifouling layer on the surface. The antifouling layer may have antibacterial properties.

[0065] The material of the protective layer 13 can be a thermoplastic polymer or a curable compound. The thermoplastic polymer can be polycarbonate, acrylic polymer, fluorinated acrylic polymer, silicone, epoxy acrylate, polystyrene, cycloolefin polymer, polypropylene, polyethylene, polyester, methylstyrene polymer, fluorene polymer, polyethylene terephthalate (PET), and acrylonitrile styrene copolymer. The curing compounds can be phenolic resins, melamine, urea resins, and alkyd resins and polyacetals.

[0066] 2 and 3, the image carrier 20 faces the light-shielding layer 12 with the transparent substrate 11 sandwiched therebetween. The image carrier 20 includes a protective layer 21 and an image recording layer 22, as shown in FIGS. 2, 3, and 5.

[0067] The protective layer 21 protects the image recording layer 22 from damage and can also serve as a substrate for the image recording layer 22. For example, when the image recording layer 22 is formed on a transparent substrate 11, the protective layer 21 can be omitted.

[0068] The protective layer 21 is transparent to light in the visible range, and is preferably colorless and transparent.

[0069] The protective layer 21 may be a sheet or a film. For example, the protective layer 21 may be a polymer sheet or a polymer film. The protective layer 21 may have a single-layer structure or a multi-layer structure. The material of the protective layer 21 may be the same as the materials exemplified for the protective layer 13.

[0070] The image recording layer 22 is provided between the transparent substrate 11 and the protective layer 21. The image recording layer 22 faces the light-shielding layer 12 with the transparent substrate 11 sandwiched therebetween. Such an arrangement is suitable for maintaining a distance between the light-shielding layer 12 and the image recording layer 22.

[0071] The image recording layer 22 includes colored portions 22P1 and 22P2. Each of the colored portions 22P1 and 22P2 exhibits higher transmittance in certain wavelength ranges within the visible range and lower transmittance in other wavelength ranges within the visible range. The colored portions 22P1 and 22P2 have different transmission spectra within the visible range. Therefore, the colored portions 22P1 and 22P2 appear to be different colors when illuminated with white light and the transmitted light is observed.

[0072] The image recording layer 22 including the colored portions 22P1 and 22P2 can be formed by partial thermal transfer of an ink ribbon, inkjet printing, electrophotography, or a combination of two or more of these. The image recording layer 22 can be formed in three colors: cyan, magenta, and yellow. Alternatively, the image recording layer 22 may be formed in four colors, including black. The image recording layer 22 may be formed in five to ten colors, including a special color. The image recording layer 22 may be formed by offset printing or screen printing. The colored portions 22P1 and 22P2 of the image recording layer 22 thus obtained contain dyes, pigments, or both. The dyes or pigments can be visible inks. The colored portions 22P1 and 22P2 can also contain functional inks. The functional inks can be pearl inks, magnetic inks, or both. These colored portions 22P1 and 22P2 can further contain other components, such as binder resins.

[0073] The image carrier 20 includes a first display region PR1 and a second display region PR2 shown in FIGS. 1 to 3 and 5. The first display region PR1 may be surrounded by the second display region PR2. The outer shape of the first display region PR1 may be a symbol, icon, flag, emblem, mark, code, letter, number, text, face image, portrait, animal, plant, legendary creature, or landmark. The second display region PR2 may be a background. The face image may be that of the owner. The letter, number, or text may be the owner's date of birth, name, or number unique to the display device. The code may also be a code unique to the display device. As shown in FIG. 5, each of the first display region PR1 and the second display region PR2 includes multiple cells C. These cells C are aligned in the length and width directions of the slit SL. That is, the cells C are located at lattice points of a two-dimensional lattice defined by a basis consisting of mutually orthogonal vectors parallel to the length and width directions of the slit SL. Note that this two-dimensional lattice forms a square or rectangular lattice. Here, as an example, it is assumed that the pitch P2 of the arrangement of the cells C in the width direction of the slit SL is 1 / 2 of the pitch P1 of the arrangement of the slit SL.

[0074] Each of the colored portions 22P1 and 22P2 is disposed within a cell C. That is, each of the colored portions 22P1 and 22P2 is located on a lattice point of a virtual two-dimensional lattice.

[0075] More specifically, in the first display region PR1, the colored portion 22P1 is not arranged in a cell C in the 2n-1th row (n is a natural number) among rows each made up of cells C aligned in the X direction. In the first display region PR1, each colored portion 22P1 is located in a cell C in the 2nth row among rows each made up of cells C aligned in the X direction.

[0076] On the other hand, in the second display region PR2, the colored portion 22P1 is not arranged in a cell C in the 2nth row among rows each made up of cells C aligned in the X direction. In the second display region PR2, each colored portion 22P1 is located in a cell C in the 2n-1th row among rows each made up of cells C aligned in the X direction.

[0077] In the first display region PR1, the colored portion 22P2 is not disposed in a cell C in the 2nth row among rows each made up of cells C aligned in the X direction. In the first display region PR1, each colored portion 22P2 is located in a cell C in the 2n-1th row among rows each made up of cells C aligned in the X direction.

[0078] On the other hand, in the second display region PR2, the colored portion 22P2 is not arranged in a cell C in the 2n-1th row among the rows each consisting of cells C aligned in the X direction. In the second display region PR2, each colored portion 22P2 is located in a cell C in the 2nth row among the rows each consisting of cells C aligned in the X direction.

[0079] In this way, in the first display region PR1 and the second display region PR2, the row of the cells C in which the colored portion 22P1 is arranged and the row of the cells C in which the colored portion 22P2 is arranged are shifted in the Y direction by the pitch P2.

[0080] When only the image carrier 20 is observed with the naked eye, the observer cannot recognize the above-mentioned misalignment, and therefore cannot distinguish the first display region PR1 from the second display region PR2. However, as will be described later, when the display 1 including the combination of the mask layer 10 and the image carrier 20 is observed with the naked eye, the first display region PR1 and the second display region PR2 can be distinguished from each other. That is, the arrangement of the colored portions 22P1 and 22P2 in the first display region PR1 and the arrangement of the colored portions 22P1 and 22P2 in the second display region PR2 form a latent image that is visualized by being partially concealed by the light-shielding layer 12.

[0081] As shown in Figures 2 and 3, the adhesive layer 30 is interposed between the mask layer 10 and the image carrier 20. The adhesive layer 30 bonds the mask layer 10 and the image carrier 20 together with the transparent substrate 11 sandwiched between them so that the light-shielding layer 12 and the image recording layer 22 face each other. The adhesive layer 30 is transparent to light in the visible range. The adhesive layer 30 is preferably colorless and transparent. The adhesive layer 30 may be a single layer made of an adhesive, or may be a multilayer including a layer made of an adhesive and a layer made of an anchoring agent.

[0082] As will be explained below, this display 1 can display different images depending on the viewing conditions.

[0083] Fig. 6 is a diagram showing an example of a viewing condition, and Fig. 7 is a diagram showing an example of an image displayed by the display device shown in Figs. 1 to 3 under the viewing condition of Fig. 6.

[0084] Under the observation conditions shown in FIG. 6, the display 1 is placed on a black surface (not shown) with the mask layer 10 positioned between the black surface and the image carrier 20. In this state, white light emitted from the light source LS is used as illumination light IL, and the display 1 is illuminated from the image carrier 20 side. An observer OB visually recognizes reflected light RL emitted from the display 1. Note that the angle of incidence of the illumination light IL on the display 1 is adjusted to a first incident angle. Also, here, the light-shielding layer has a specular reflecting surface that specularly reflects the illumination light IL, and the observer OB visually recognizes specularly reflected light as the reflected light RL.

[0085] As described above, in the first display region PR1 and the second display region PR2, the row of the cells C in which the colored portion 22P1 is arranged and the row of the cells C in which the colored portion 22P2 is arranged are shifted by the pitch P2 in the Y direction. That is, as shown in Figures 2 and 3, the position of the colored portion 22P1 with respect to the slit SL is shifted by the pitch P2 relative to the first display region PR1 of the display body 1 and the second display region PR2 of the display body 1. Similarly, the position of the colored portion 22P2 with respect to the slit SL is shifted by the pitch P2 relative to the first display region PR1 of the display body 1 and the second display region PR2 of the display body 1.

[0086] 6, for example, a portion of the illumination light IL incident on the first display region PR1 passes through the colored portion 22P1 and is reflected by the light-shielding layer 12. The reflected light RL reflected by the light-shielding layer 12 passes through the colored portion 22P1 adjacent to the above-mentioned colored portion 22P1 and can be viewed by the observer OB. The remainder of the illumination light IL incident on the first display region PR1 passes through the colored portion 22P2, then passes through the slit SL, and is absorbed by the black surface.

[0087] In contrast, a portion of the illumination light IL that enters the second display region PR2 passes through the colored portion 22P2 and is reflected by the light-shielding layer 12. The reflected light RL reflected by the light-shielding layer 12 passes through the colored portion 22P2 adjacent to the above-mentioned colored portion 22P2 and is viewed by the observer OB. The remainder of the illumination light IL that enters the second display region PR2 passes through the colored portion 22P1, then passes through the slit SL, and is absorbed by the black surface.

[0088] In this way, the reflected light RL from the first display region PR1 of the display body 1 is colored by the colored portion 22P1. In contrast, the reflected light RL from the second display region PR2 of the display body 1 is colored by the colored portion 22P2. Therefore, as shown in FIG. 7, these regions appear to have different colors. In other words, the latent image is visualized.

[0089] Fig. 8 is a diagram schematically showing another example of the viewing conditions, and Fig. 9 is a diagram showing an example of an image displayed by the display device shown in Figs. 1 to 3 under the viewing conditions of Fig. 8.

[0090] The observation conditions shown in Figure 8 are the same as those shown in Figure 6, except that the incident angle of the illumination light IL is changed from the first incident angle to the second incident angle, and the observation direction by the observer OB is changed accordingly.

[0091] 8, a portion of the illumination light IL incident on the first display region PR1 passes through the colored portion 22P2 and is reflected by the light-shielding layer 12. The reflected light RL reflected by the light-shielding layer 12 passes through the colored portion 22P2 adjacent to the above-mentioned colored portion 22P2 and can be viewed by the observer OB. The remainder of the illumination light IL incident on the first display region PR1 passes through the colored portion 22P1, then passes through the slit SL, and is absorbed by the black surface.

[0092] In contrast, a portion of the illumination light IL that enters the second display region PR2 passes through the colored portion 22P1 and is reflected by the light-shielding layer 12. The reflected light RL reflected by the light-shielding layer 12 passes through the colored portion 22P1 adjacent to the above-mentioned colored portion 22P1 and is viewed by the observer OB. The remainder of the illumination light IL that enters the second display region PR2 passes through the colored portion 22P2, then passes through the slit SL, and is absorbed by the black surface.

[0093] In this way, the reflected light RL from the portion of the display 1 corresponding to the first display region PR1 is colored by the colored portion 22P2. In contrast, the reflected light RL from the portion of the display 1 corresponding to the second display region PR2 is colored by the colored portion 22P1. Therefore, as shown in FIG. 9, these regions appear to be different colors. This causes the latent image to become visible. Furthermore, as shown in FIGS. 7 and 9, the visible image that can be observed under the observation conditions shown in FIG. 8 has colors that are inverted from the visible image that can be observed under the observation conditions shown in FIG. 6.

[0094] In this way, the latent image of the display 1 is visualized under the observation conditions shown in Figures 6 and 8. The color of the visualized image of the display 1 changes as the observation conditions are changed as shown in Figures 6 and 8.

[0095] FIG. 10 is a diagram schematically showing still another example of the observation conditions. 10, white light emitted by a light source LS is used as illumination light IL to illuminate the display 1 from the side of the mask layer 10. An observer OB observes transmitted light TL.

[0096] The light-shielding layer 12 transmits the illumination light IL at the positions of the slits SL and blocks the illumination light IL at other positions. In the portion of the display 1 corresponding to the first display region PR1, the illumination light IL that has transmitted through the slits SL passes through, for example, the colored portion 22P1 and is then visible to the viewer OB as transmitted light TL. In this case, in the portion of the display 1 corresponding to the second display region PR2, the illumination light IL that has transmitted through the slits SL passes through the colored portion 22P2 and is then visible to the viewer OB as transmitted light TL. Therefore, in this case, the latent image is visualized as shown in FIG. 7.

[0097] When the display 1 is slightly rotated around an axis parallel to the X direction, the position at which the illumination light IL transmitted through the slit SL enters the image recording layer 22 in the portion of the display 1 corresponding to the first display region PR1 changes from the position of the colored portion 22P1 to the position of the colored portion 22P2. Also, in the portion of the display 1 corresponding to the second display region PR2, the position at which the illumination light IL transmitted through the slit SL enters the image recording layer 22 changes from the position of the colored portion 22P2 to the position of the colored portion 22P1. As a result, the visible image displayed by the display 1 changes from the visible image shown in FIG. 7 to the visible image shown in FIG. 9.

[0098] FIG. 11 is a diagram schematically showing still another example of the observation conditions. Under the observation conditions shown in FIG. 11, the display 1 is placed on a reflective surface (not shown) with the image carrier 20 positioned between the reflective surface and the mask layer 10. In this state, white light emitted from a light source LS is used as illumination light IL to illuminate the display 1 from the mask layer 10 side. An observer OB visually recognizes reflected light RL emitted from the display 1. Note that the angle of incidence of the illumination light IL on the display 1 is adjusted to a third incident angle. It is also assumed that the observer OB visually recognizes specularly reflected light as the reflected light RL. It is also assumed that the reflective surface on which the display 1 is placed has the same reflective properties as the light-shielding layer 12.

[0099] FIG. 12 is a diagram schematically showing still another example of the observation conditions. The observation conditions shown in Figure 12 are the same as those shown in Figure 11, except that the incident angle of the illumination light IL is changed from the third incident angle to the fourth incident angle, and the observation direction by the observer OB is changed accordingly.

[0100] 11 and 12, the illumination light IL passing through the slit SL is reflected by the reflective surface on which the display unit 1 is placed. As described above, this reflective surface has the same reflective properties as the light-shielding layer 12. Therefore, the concealing effect of the light-shielding layer 12 is not produced or is not very pronounced. Therefore, under either of the viewing conditions shown in FIGS. 11 and 12, the portion of the display unit 1 corresponding to the first display region PR1 and the portion of the display unit 1 corresponding to the second display region PR2 appear to be the same color. In other words, even if the angle of incidence of the illumination light IL is changed, the latent image does not become visible.

[0101] In this way, the display 1 can display an image according to the viewing conditions. That is, the display 1 can display a special image in which the image changes depending on the viewing conditions.

[0102] <First Modification> The display 1 can be modified in various ways. Fig. 13 is a plan view schematically showing a mask layer of a display according to a modified example, Fig. 14 is a plan view schematically showing an image recording layer of a display according to a modified example, and Fig. 15 is a plan view schematically showing a display according to a modified example.

[0103] In the mask layer 10 shown in Fig. 13, the width W1 and the width W2 are 2 / 3 and 1 / 3 of the pitch P1, respectively. Except for this, the mask layer 10 shown in Fig. 13 is similar to the mask layer 10 described with reference to Figs. 2 to 4, etc.

[0104] The image carrier 20 shown in FIG. 14 is similar to the image carrier 20 described with reference to FIGS. 2, 3, 5, etc., except for the following points.

[0105] That is, in the image carrier 20 shown in FIG. 14, the pitch P2 is shifted from 1 / 3m (m is a natural number) of the pitch P1.

[0106] In addition to the colored portions 22P1 and 22P2, the image recording layer 22 further includes a colored portion 22P3. The colored portion 22P3 exhibits higher transmittance in certain wavelength ranges within the visible range and lower transmittance in other wavelength ranges within the visible range. The colored portion 22P3 has a different transmission spectrum within the visible range from the colored portions 22P1 and 22P2. Therefore, the colored portions 22P1 to 22P3 appear to be different colors when illuminated with white light and the transmitted light is observed.

[0107] In the first display region PR1, among rows consisting of cells C lined up in the X direction, the cell C in the 3n-1th row (n is a natural number) is a cell for the coloring section 22P1, the cell C in the 3nth row is a cell for the coloring section 22P2, and the cell C in the 3n+1th row is a cell for the coloring section 22P3. That is, in the first display region PR1, among rows consisting of cells C lined up in the X direction, each coloring section 22P1 is not located within the cell C in the 3nth or 3n+1th row, but is located within the cell C in the 3n-1th row. Also, in the first display region PR1, among rows consisting of cells C lined up in the X direction, each coloring section 22P2 is not located within the cell C in the 3n-1th or 3n+1th row, but is located within the cell C in the 3nth row. In the first display region PR1, each of the colored portions 22P3 is not located in the cell C in the 3n-1th and 3nth rows of the rows each consisting of cells C aligned in the X direction, but is located in the cell C in the 3n+1th row.

[0108] On the other hand, in the second display region PR2, among the rows consisting of cells C aligned in the X direction, the cell C in the 3n-2 row is a cell for the coloring section 22P1, the cell C in the 3n-1 row is a cell for the coloring section 22P2, and the cell C in the 3n row is a cell for the coloring section 22P3. That is, in the second display region PR2, among the rows consisting of cells C aligned in the X direction, each coloring section 22P1 is not located within the cell C in the 3n-1th and 3nth rows, but is located within the cell C in the 3n-2th row. Also, in the second display region PR2, among the rows consisting of cells C aligned in the X direction, each coloring section 22P2 is not located within the cell C in the 3n-2th and 3nth rows, but is located within the cell C in the 3n-1th row. In the second display region PR2, each of the colored portions 22P3 is not located in the cell C in the 3n-2th and 3n-1st rows of the rows each consisting of cells C aligned in the X direction, but is located in the cell C in the 3n-th row.

[0109] In this display 1, the pitch P1 of the slits SL is offset from 3m times the pitch P2 of the slits SL in the Y direction of the cells C. Therefore, in each of the first display region PR1 and the second display region PR2, the relative positions of the colored portions 22P1 to 22P3 with respect to the slits SL change in the direction of the slits SL. Therefore, when this structure is adopted, the image displayed by the display 1 changes color in the direction of the slits SL in both the portion corresponding to the first display region PR1 and the portion corresponding to the second display region PR2. That is, when the above structure is adopted, rainbow stripes appear in the image displayed by the display 1 due to the difference between the pitch P1 and the pitch P2 of the slits SL in both the portion corresponding to the first display region PR1 and the portion corresponding to the second display region PR2. These rainbow stripes are a special image display that changes depending on the viewing conditions.

[0110] It is preferable that the pitch P1 of the arrangement of the slits SL and the pitch P2 of the arrangement of the cells C in the arrangement direction of the slits SL satisfy the relationship shown in the following inequality (1) or (2).

[0111] 0%<(P1-3×P2) / (3×P2)<25% …(1) 0%<(3×P2-P1) / (3×P2)<25% …(2) Increasing the deviation of pitch P1 from three times pitch P2 reduces the period of the rainbow stripes, making it difficult to distinguish between the portion corresponding to first display region PR1 and the portion corresponding to second display region PR2 under conditions in which a visible image should be displayed.

[0112] <Second embodiment of the present invention> FIG. 16 is a cross-sectional view schematically showing a display according to a second embodiment of the present invention.

[0113] The display member 1 shown in FIG. 16 includes a mask layer 10, a first image carrier 20A, a second image carrier 20B, a first adhesive layer 30A, and a second adhesive layer 30B.

[0114] The mask layer 10 includes a first transparent substrate 11A, a second transparent substrate 11B, a light-shielding layer 12, and an adhesive layer .

[0115] The first transparent substrate 11A transmits light in part or all of the visible range. The first transparent substrate 11A is preferably colorless and transparent. The materials for the first transparent substrate 11A can be, for example, those described for the transparent substrate 11.

[0116] The light-shielding layer 12 is provided on one main surface of the first transparent base material 11A. The light-shielding layer 12 is the same as that described in the first embodiment. As a specific example, the light-shielding layer 12 is made of metal and is a light-shielding reflector provided with slits SL.

[0117] The second transparent substrate 11B faces the first transparent substrate 11A with the light-shielding layer 12 and the adhesive layer 14 sandwiched therebetween. The second transparent substrate 11B transmits light in part or all of the visible range. The second transparent substrate 11B is preferably colorless and transparent. The materials described for the transparent substrate 11 can be applied to the second transparent substrate 11B.

[0118] The adhesive layer 14 is interposed between the first transparent substrate 11A and the second transparent substrate 11B, and bonds the first transparent substrate 11A and the second transparent substrate 11B together. The adhesive layer 14 transmits light in part or all of the visible range. The adhesive layer 14 is preferably colorless and transparent. The adhesive layer 14 may have a single-layer structure made of an adhesive, or may be a multilayer structure including a layer made of an adhesive and a layer made of an anchoring agent.

[0119] The first image carrier 20A faces the light-shielding layer 12 with the first transparent substrate 11A sandwiched therebetween. The first image carrier 20A includes, in order from the first transparent substrate 11A side, an image recording layer 22 and a protective layer 21. The protective layer 21 and the image recording layer 22 of the first image carrier 20A are the same as those described in the first embodiment.

[0120] The second image carrier 20B faces the light-shielding layer 12 with the second transparent substrate 11B sandwiched therebetween. The second image carrier 20B includes, in order from the second transparent substrate 11B side, an image recording layer 22 and a protective layer 21. The protective layer 21 and the image recording layer 22 of the second image carrier 20B are the same as those described in the first embodiment.

[0121] The first adhesive layer 30A is interposed between the mask layer 10 and the first image carrier 20A. The first adhesive layer 30A bonds the mask layer 10 and the first image carrier 20A together with the first transparent substrate 11A sandwiched between them so that the light-shielding layer 12 and the image recording layer 22 of the first image carrier 20A face each other. The first adhesive layer 30A transmits light in part or all of the visible range. The first adhesive layer 30A is preferably colorless and transparent. The first adhesive layer 30A may be a single layer made of an adhesive, or may be a multilayer including a layer made of an adhesive and a layer made of an anchoring agent.

[0122] The second adhesive layer 30B is interposed between the mask layer 10 and the second image carrier 20B. The second adhesive layer 30B bonds the mask layer 10 and the second image carrier 20B together with the second transparent substrate 11B sandwiched between them so that the light-shielding layer 12 and the image recording layer 22 of the second image carrier 20B face each other. The second adhesive layer 30B transmits light in part or all of the visible range. The second adhesive layer 30B is preferably colorless and transparent. The second adhesive layer 30B may be a single layer made of an adhesive, or may be a multilayer including a layer made of an adhesive and a layer made of an anchoring agent.

[0123] In this display member 1, the distance from the light-shielding layer 12 to the image recording layer 22 of the second image carrier 20B is equal to the distance from the light-shielding layer 12 to the image recording layer 22 of the first image carrier 20A. Furthermore, the positions of the orthogonal projections of the colored portions 22P1 and 22P1 included in the image recording layer 22 of the second image carrier 20B onto a plane parallel to the main surface of the light-shielding layer 12 are equal to the positions of the orthogonal projections of the colored portions 22P1 and 22P1 included in the image recording layer 22 of the first image carrier 20A onto the same plane.

[0124] As will be explained below, this display 1 can display different images depending on the viewing conditions.

[0125] For example, under the same observation conditions as those described with reference to FIG. 6, except that the display 1 is placed so that the mask layer 10 and the second image carrier 20B are positioned between the black surface and the first image carrier 20A, the display 1 displays the same visible image as that described with reference to FIG. 7.

[0126] Under the same observation conditions as those described with reference to FIG. 8, the display 1 displays the same visible image as that described with reference to FIG. 9, except that the display 1 is placed so that the mask layer 10 and the second image carrier 20B are positioned between the black surface and the first image carrier 20A.

[0127] Under the same observation conditions as those described with reference to FIG. 6, the display 1 displays the same visible image as that described with reference to FIG. 7, except that the display 1 is placed so that the mask layer 10 and the first image carrier 20A are positioned between the black surface and the second image carrier 20B.

[0128] Under the same observation conditions as those described with reference to FIG. 8, the display 1 displays the same visible image as that described with reference to FIG. 9, except that the display 1 is placed so that the mask layer 10 and the first image carrier 20A are positioned between the black surface and the second image carrier 20B.

[0129] 10, except that the display 1 is placed so that the first image carrier 20A is located between the mask layer 10 and the observer OB, and the second image carrier 20B is located between the mask layer 10 and the light source LS. Under the same observation conditions as those described with reference to Fig. 10, the display 1 displays the same visible image as that described with reference to Fig. 7. Then, in this state, when the display 1 is slightly rotated around an axis parallel to the X direction, the visible image displayed by the display 1 changes from the visible image shown in Fig. 7 to the visible image shown in Fig. 9.

[0130] In this way, the display 1 can display various images depending on the viewing conditions, that is, the display 1 can display special images.

[0131] <Second Modification> In the second modification, the display 1 according to the second embodiment is modified as follows. 16, part of the colored portion 22P1 is omitted and part of the colored portion 22P2 is omitted from the image recording layer 22 of the first image carrier 20A. Also, part of the colored portion 22P1 is omitted and part of the colored portion 22P2 is omitted from the image recording layer 22 of the second image carrier 20B.

[0132] In the image recording layer 22 of the second image carrier 20B, the colored portion 22P1 is omitted at a position corresponding to the colored portion 22P1 remaining in the image recording layer 22 of the first image carrier 20A, and the colored portion 22P1 remains at a position corresponding to the colored portion 22P1 omitted from the image recording layer 22 of the first image carrier 20A. In the image recording layer 22 of the second image carrier 20B, the colored portion 22P2 is omitted at a position corresponding to the colored portion 22P2 remaining in the image recording layer 22 of the first image carrier 20A, and the colored portion 22P2 remains at a position corresponding to the colored portion 22P2 omitted from the image recording layer 22 of the first image carrier 20A.

[0133] As will be described below, this display 1 can display an image different from that of the display 1 according to the second embodiment.

[0134] For example, under the same observation conditions as those described with reference to FIG. 6, except that the display body 1 is placed so that the mask layer 10 and the second image carrier 20B are positioned between the black surface and the first image carrier 20A, the display body 1 displays a visible image that is partially different from the visible image described with reference to FIG. 7.

[0135] Under the same observation conditions as those described with reference to Figure 8, except that the display 1 is placed so that the mask layer 10 and the second image carrier 20B are positioned between the black surface and the first image carrier 20A, the display 1 displays a visible image that is partially different from the visible image described with reference to Figure 9.

[0136] Under the same observation conditions as those described with reference to FIG. 6, except that the display 1 is placed so that the mask layer 10 and the first image carrier 20A are positioned between the black surface and the second image carrier 20B, the display 1 displays a visible image that is partially different from the visible image described with reference to FIG. 7.

[0137] Under the same observation conditions as those described with reference to Figure 8, except that the display 1 is placed so that the mask layer 10 and the first image carrier 20A are positioned between the black surface and the second image carrier 20B, the display 1 displays a visible image that is partially different from the visible image described with reference to Figure 9.

[0138] 10, except that the display 1 is placed so that the first image carrier 20A is located between the mask layer 10 and the observer OB, and the second image carrier 20B is located between the mask layer 10 and the light source LS. Under the same observation conditions as those described with reference to Fig. 10, the display 1 displays the same visible image as that described with reference to Fig. 7. Then, in this state, when the display 1 is slightly rotated around an axis parallel to the X direction, the visible image displayed by the display 1 changes from the visible image shown in Fig. 7 to the visible image shown in Fig. 9.

[0139] In this way, the display 1 can display various images depending on the observation conditions. Furthermore, the display 1 displays different visible images when observed with reflected light and when observed with transmitted light under the observation conditions. In other words, the display 1 is capable of displaying special images.

[0140] <Third Modification> In the second modification, the display 1 according to the second embodiment is modified as follows. 16, the arrangement of the first display region PR1 and the second display region PR2 in the image recording layer 22 of the second image carrier 20B is made different from the arrangement of the first display region PR1 and the second display region PR2 in the image recording layer 22 of the first image carrier 20A. For example, in the image recording layer 22 of the first image carrier 20A, the first display region PR1 is circular, and the second display region PR2 is provided so as to surround the first display region PR1. In addition, in the image recording layer 22 of the second image carrier 20B, the first display region PR1 is star-shaped, and the second display region PR2 is provided so as to surround the first display region PR1.

[0141] As will be described below, this display 1 can display an image different from that of the display 1 according to the second embodiment.

[0142] Under the same observation conditions as those described with reference to Figure 6, except that the display 1 is placed so that the mask layer 10 and the second image carrier 20B are positioned between the black surface and the first image carrier 20A, the display 1 displays a visible image including a circular pattern colored in the color of the colored portion 22P1 and a background pattern colored in the color of the colored portion 22P2.

[0143] Under the same observation conditions as those described with reference to Figure 8, except that the display 1 is placed so that the mask layer 10 and the second image carrier 20B are positioned between the black surface and the first image carrier 20A, the display 1 displays a visible image including a circular pattern colored in the color of the colored portion 22P2 and a background pattern colored in the color of the colored portion 22P1.

[0144] Under the same observation conditions as those described with reference to Figure 6, except that the display 1 is placed so that the mask layer 10 and the first image carrier 20A are positioned between the black surface and the second image carrier 20B, the display 1 displays a visible image including a star pattern colored in the color of the colored portion 22P1 and a background pattern colored in the color of the colored portion 22P2.

[0145] Under the same observation conditions as those described with reference to Figure 8, except that the display 1 is placed so that the mask layer 10 and the first image carrier 20A are positioned between the black surface and the second image carrier 20B, the display 1 displays a visible image including a star pattern colored in the color of the colored portion 22P2 and a background pattern colored in the color of the colored portion 22P1.

[0146] 10 , except that the display 1 is installed so that the first image carrier 20A is located between the mask layer 10 and the viewer OB and the second image carrier 20B is located between the mask layer 10 and the light source LS, the display 1 displays a superimposed image including a circular pattern colored in the color of the colored portion 22P1 and a background pattern colored in the color of the colored portion 22P2, and a superimposed image including a star-shaped pattern colored in the color of the colored portion 22P1 and a background pattern colored in the color of the colored portion 22P2. When the display 1 is rotated slightly around an axis parallel to the X direction in this state, the image displayed by the display 1 changes to a superimposed image including a circular pattern colored in the color of the colored portion 22P2 and a background pattern colored in the color of the colored portion 22P1, and a star-shaped pattern colored in the color of the colored portion 22P2 and a background pattern colored in the color of the colored portion 22P1.

[0147] In this way, the display 1 can display various images depending on the observation conditions. Furthermore, the display 1 displays different visible images when observed with reflected light and when observed with transmitted light under the observation conditions. In other words, the display 1 can display special images in which the visible image changes depending on the observation conditions.

[0148] <Other variations> The display 1 according to the above-described embodiment and modified example can be further modified. For example, in the display 1 of the first embodiment, the colored portion 22P2 may be omitted. The display 1 of the second embodiment may employ the configuration described in the first modified example.

[0149] In any of the display units 1, in addition to or instead of a configuration in which the color of the visible image changes in response to changes in the angle of incidence of the illumination light IL or the tilt angle of the display unit 1, a configuration in which the shape of the pattern included in the visible image changes in response to changes in the angle of incidence of the illumination light IL or the tilt angle of the display unit 1 may be employed. The display unit 1 may also be configured to display a moving image by changing the angle of incidence of the illumination light IL or the tilt angle of the display unit 1.

[0150] A light absorbing material may be used instead of a reflector as the light-shielding layer 12. For example, when the light-shielding layer 12 of the display 1 according to the first embodiment is a light absorbing material, under the observation conditions described with reference to Fig. 6 and the observation conditions described with reference to Fig. 8, the portion of the display 1 corresponding to the first display region PR1 and the portion of the display 1 corresponding to the second display region PR2 both appear black. In other words, these portions appear to be the same color and cannot be distinguished from each other, so the latent image is not visualized.

[0151] Under the observation conditions described with reference to Fig. 10, this display 1 displays the same visible image as that described with reference to Fig. 7. Then, when the display 1 is rotated slightly around an axis parallel to the X direction in this state, the visible image displayed by the display 1 changes from the visible image shown in Fig. 7 to the visible image shown in Fig. 9.

[0152] Furthermore, under the observation conditions described with reference to Fig. 11, the display 1 displays the visible image described with reference to Fig. 7. And under the observation conditions described with reference to Fig. 12, the display 1 displays the visible image described with reference to Fig. 9.

[0153] In this way, the display 1 using a light absorbing material instead of a reflector as the light blocking layer 12 can also display various images depending on the viewing conditions.

[0154] When the light-shielding layer 12 is a reflector, the reflector may have a specular reflection surface and specularly reflect the illumination light, or may be a light-scattering layer that scatters the illumination light. Specular reflection makes the change in the visible image clear, while a light-scattering layer for the light-shielding layer 12 widens the angle range in which the visible image displayed by reflected light can be viewed.

[0155] The image recording layer 22 may generate moiré when overlapped with the light-shielding layer 12. For example, if the pitch P1 of the slit SL array is not an integer multiple of the pitch P2 of the cells C in the slit SL array direction, or if the length direction of the slit SL is tilted with respect to the cell C array direction, a visible image containing moiré may be displayed. Moiré may occur when the image recording layer of the second or third image carrier is overlapped with the light-shielding layer 12, but may not occur when the image recording layer of the first image carrier is overlapped with the light-shielding layer 12. Conversely, moiré may occur when the image recording layer of the first image carrier is overlapped with the light-shielding layer 12, but may not occur when the image recording layer of the second or third image carrier is overlapped with the light-shielding layer 12. This results in a clear difference in the impression of the display on the front and back, making it difficult to confuse the front and back even under adverse conditions. Moire patterns may also be generated by overlapping the image recording layers of the first, second, and third image carriers with the light-shielding layer 12. The moire patterns generated by overlapping the image recording layer of the first image carrier with the light-shielding layer 12, the moire patterns generated by overlapping the image recording layer of the second image carrier with the light-shielding layer 12, and the moire patterns generated by overlapping the image recording layer of the third image carrier with the light-shielding layer 12 may be different. The moire patterns generated by overlapping the image recording layer of the first image carrier with the light-shielding layer 12, the moire patterns generated by overlapping the image recording layer of the second image carrier with the light-shielding layer 12, and the moire patterns generated by overlapping the image recording layer of the third image carrier with the light-shielding layer 12 may be similar. Different moire patterns make counterfeiting more difficult, while similar moire patterns create a stronger visual impression.

[0156] As described above, various modifications are possible for the display 1 according to the embodiments and modifications embodying the present invention. The display of the present invention can combine the configurations of the first and second embodiments described above and have the properties, characteristics, functions, and effects described above for the first and second embodiments. Furthermore, the display of the present invention can have the properties, characteristics, functions, and effects described above for the first or second embodiment and the properties, characteristics, functions, and effects of one or more of the modifications described above by modifying part or all of the first and second embodiments.

[0157] <Application example> The display medium 1 can be used as an identification (ID) card such as an employee ID card, a driver's license, or a student ID card. The display medium 1 can also be used as a security such as a banknote, a stock certificate, a gift certificate, a train ticket, or an admission ticket. The display medium 1 can also be used as a payment card, a credit card, an ATM card, or a membership card. The display medium 1 can also be used as a data page for a passport or visa.

[0158] FIG. 17 is a plan view schematically showing an application example of a display.

[0159] Fig. 17 illustrates a booklet 100 as an application example in which a display is installed. Note that Fig. 17 illustrates the booklet 100 in an open state.

[0160] Here, the booklet 100 is a passport, but the booklet 100 may also be another item such as a bankbook.

[0161] Booklet 100 includes signatures 110 and a cover 120 . A signature 110 is made up of one or more sheets 111. A signature 110 is formed by folding in half a single sheet 111 or a stack of multiple sheets 111. Each sheet 111 may be a piece of paper, a polymer sheet, or a composite thereof.

[0162] The cover 120 is folded in half. The cover 120 and the quire 110 are overlapped so that the quire 110 is sandwiched between the cover 120 when the booklet 100 is closed, and are integrated at the fold by binding or the like.

[0163] One of the sheets 111 has a first portion A1, a second portion A2, and a third portion A3.

[0164] The second part A2 is a part where a facial photograph is recorded. The third part A3 is a part where information that can be optically recognized is recorded. The third part A3 can be recorded by printing. The first portion A1 is spaced apart from the second portion A2 and the third portion A3. The first portion A1 is the portion to which the structure employed for the display 1 is applied or where the display 1 is placed. When the sheet 111 includes a polymer sheet, the transparent substrate 11 or a laminate of the first transparent substrate 11A and the second transparent substrate 11B can be used as this polymer sheet, and the structure employed for the display 1 can be applied to a part of it (the first portion A1). Alternatively, when a piece of paper is used as the sheet 111, a window (the first portion A1) can be provided in the piece of paper, and the display 1 can be placed at the position of this window.

[0165] This sheet 111 may have built-in an IC (integrated circuit) chip on which personal information is recorded, an antenna that enables contactless communication between this IC chip and an external device, etc. The IC chip and antenna are installed in a part of sheet 111 other than first part A1.

[0166] FIG. 18 is a plan view schematically showing another application example of the display. FIG. 18 shows a card 200 as another application example in which a display is installed.

[0167] This card 200 is an IC card, and includes a card body 210 and an IC chip (not shown).

[0168] The card body 210 includes a transparent substrate 11 or a laminate of a first transparent substrate 11A and a second transparent substrate 11B as the card substrate. The card body 210 has a first portion A1 and a fourth portion A4 that are spaced apart from each other. The display 1 is installed in the first portion A1. The card body 210 has an IC chip built into the fourth portion A4.

[0169] FIG. 19 is a plan view schematically showing still another application example of a display. FIG. 19 illustrates a card 200 as yet another application example of a display body.

[0170] This card 200 is a magnetic card and includes a card body 210 and a strip-shaped magnetic recording layer 220.

[0171] The card body 210 includes, as the card substrate, a transparent substrate 11 or a laminate of a first transparent substrate 11A and a second transparent substrate 11B. The card body 210 has a first portion A1. The structure adopted for the display 1 is applied to the first portion A1. The magnetic recording layer 220 is provided on the card body 210 at a position spaced apart from the first portion A1.

[0172] FIG. 20 is a plan view schematically showing still another application example of the display. FIG. 20 illustrates a card 200 as yet another application example of a display body.

[0173] This card 200 is a magnetic card with an IC chip. The card 200 includes a card body 210, a strip-shaped magnetic recording layer 220, and an IC chip (not shown).

[0174] The card body 210 includes a transparent substrate 11 or a laminate of a first transparent substrate 11A and a second transparent substrate 11B as the card substrate. The card body 210 has a first portion A1 and a fourth portion A4 that are spaced apart from each other. The display 1 is installed in the first portion A1. The card body 210 has an IC chip built into the fourth portion A4. The magnetic recording layer 220 is provided on the card body 210 at a position spaced apart from the first portion A1. In this way, the display 1 can be used in a variety of applications. [Explanation of symbols]

[0175] 1...display body, 10...mask layer, 11...transparent substrate, 11A...first transparent substrate, 11B...second transparent substrate, 12...light-shielding layer, 13...protective layer, 14...adhesive layer, 20...image carrier, 20A...first image carrier, 20B...second image carrier, 21...protective layer, 22...image recording layer, 22P1...colored portion, 22P2...colored portion, 22P3...colored portion, 30...adhesive layer, 30A...first adhesive layer, 30B...second 2 adhesive layer, 100...booklet, 110...signature, 111...sheet, 120...cover, 200...card, 210...card body, 220...magnetic recording layer, A1...first part, A2...second part, A3...third part, A4...fourth part, C...cell, IL...illuminating light, LS...light source, OB...observer, PR1...first display area, PR2...second display area, RL...reflected light, SL...slit, TL...transmitted light.

Claims

1. a light-shielding layer provided with a plurality of slits arranged at intervals in the width direction; a first image recording layer facing one main surface of the light-shielding layer across a gap, on which a first latent image is recorded, the first latent image being made visible by being partially concealed by the light-shielding layer; a second image recording layer facing the other main surface of the light-shielding layer across a gap, on which a second latent image is recorded, the second latent image being made visible by being partially concealed by the light-shielding layer; A display body comprising:

2. 2. The display according to claim 1, wherein the distance from the light-shielding layer to the first image recording layer is in the range of 50 [mu]m to 2 mm.

3. 3. The display body according to claim 1, wherein the first visible image, which is made visible by partially concealing the first latent image with the light-shielding layer, changes at least one of its color and shape by tilting the display body around an axis parallel to the longitudinal direction of the plurality of slits.

4. 4. The display according to claim 1, wherein the first latent image is partially hidden by the light-shielding layer, thereby causing a moire pattern.

5. 4. The display according to claim 1, further comprising a transparent substrate interposed between the light-shielding layer and the first image recording layer.

6. The display body according to any one of claims 1 to 5, wherein the second visible image, which is made visible by partially concealing the second latent image with the light-shielding layer, changes at least one of its color and shape by tilting the display body around an axis parallel to the longitudinal direction of the plurality of slits.

7. 7. The display according to claim 1, wherein the second latent image is partially hidden by the light-shielding layer, thereby causing a moire pattern.

8. 8. The display according to claim 1, wherein the distance from the light-shielding layer to the second image recording layer is in the range of 50 [mu]m to 2 mm.

9. a first transparent substrate interposed between the light-shielding layer and the first image-recording layer; a second transparent substrate interposed between the light-shielding layer and the second image-recording layer; The display according to any one of claims 1 to 8, further comprising:

10. A light-shielding layer having a plurality of slits arranged at intervals in the width direction; an image carrier including a first image recording layer facing one main surface of the light-shielding layer across a gap, the first image recording layer having a first latent image recorded thereon, the first latent image being made visible by being partially concealed by the light-shielding layer; A display comprising: the first image recording layer includes a plurality of first colored portions and a plurality of second colored portions each having a transmission spectrum in a visible range different from that of the plurality of first colored portions, the image carrier includes a first display area and a second display area each including a plurality of cells arranged in a first direction and a second direction, In each of the first display region and the second display region, rows of cells arranged in the first direction, in which the first colored portions are arranged in these cells, and rows of cells arranged in the first direction, in which the second colored portions are arranged in these cells, are alternately arranged in the second direction, and in the first display region and the second display region, the positions of the rows in which the first colored portions are arranged in the cells and the positions of the rows in which the second colored portions are arranged in the cells are shifted in the second direction, The length direction of the plurality of slits is tilted with respect to the arrangement direction of the plurality of cells, thereby causing the display to display a visible image including moire as the visualized first latent image.

11. 11. The display according to claim 1, wherein the pitch P1 of the plurality of slits is in the range of 50 to 500 [mu]m.

12. 12. The display according to claim 1, wherein a ratio W2 / P1 of a width W2 of the plurality of slits to a pitch P1 of the plurality of slits is in the range of 1 / 5 to 2 / 3.

13. 13. The display according to claim 1, wherein the light-shielding layer is a reflector.

14. 14. The display according to claim 1, wherein the light-shielding layer is a metal vapor deposition layer.

15. The display body according to any one of claims 1 to 12, wherein the light-shielding layer includes a colored pattern formed by laser beam drawing on a layer containing a thermosensitive coloring agent, or includes a black pattern formed by carbonization by laser engraving.

16. A card on which the display body according to any one of claims 1 to 15 is mounted.

17. A data page of a booklet on which the display according to any one of claims 1 to 15 is installed.

Images