JP5482391B2 - Image display body and information medium - Google Patents

Description

  The present invention relates to an image display body and an information medium having a highly secure anti-counterfeit function that is easy to determine with the naked eye.

  It is desirable that securities such as passports, credit cards, ID cards, gift certificates and checks are difficult to counterfeit. For this reason, such an article is difficult to forge or imitate itself, and a label that can be easily distinguished from a forgery or counterfeit is attached to suppress forgery.

  Further, in recent years, there is a problem in that counterfeit products such as brand products are distributed in addition to the above-mentioned products, so that the demand for the above-described anti-counterfeit technology is increasing.

  A diffraction grating pattern is known as a forgery prevention technique. The diffraction grating pattern can change the pattern according to the observation angle or display a three-dimensional image by controlling the direction, angle, brightness, and the like of diffracting light.

As a method for producing a master plate of a diffraction grating pattern, an electron beam exposure apparatus is used, and by computer control, an XY stage on which a planar substrate coated with an electron beam resist is placed is moved, There is a method of forming a diffraction grating pattern on the surface of a substrate (see, for example, Patent Document 1).
Here, as a parameter of the diffraction grating,
(1) Spatial frequency of diffraction grating (pitch of grating line)
(2) Direction of diffraction grating (direction of grating line)
(3) Diffraction grating drawing area (arrangement of diffraction grating pattern)
There are three.
And
In accordance with (1), the color at which the diffraction grating pattern appears shining with respect to a fixed point changes,
In accordance with (2), the direction in which the diffraction grating pattern appears shining changes,
In accordance with (3), a display pattern (picture, character, etc.) is determined.
Therefore, by dividing the surface of the substrate into small regions of about several tens to several hundreds of μm and changing these parameters in various regions, it is possible to express pictures, characters, and the like.

  It is also possible to use a light scattering structure pattern instead of the diffraction grating pattern. In the following, the meaning of “pattern” includes the meanings of both the diffraction grating pattern and the light scattering structure pattern.

A metal stamper is produced by a method such as electroforming from an original plate having a concavo-convex shape produced by the above method, and a thermoplastic resin or A photo-curing resin is applied, a metal stamper is brought into close contact, and heat or light is applied to soften or harden the resin to replicate the pattern.
Since the replicated pattern is usually transparent, after providing a light reflecting layer by a method such as vapor deposition of a metal or dielectric thin film layer such as aluminum, an adhesive layer is formed on a substrate such as paper or plastic film. A sticker or a transfer foil is attached, and if necessary, a protective layer is provided to prevent the printed layer and pattern layer from being stained and scratched, whereby securities and cards are produced.

By the way, there is a technique called changing as a method of expressing an image that changes according to the incident angle of illumination light or the observation angle of an observer on a flat substrate.
As a technique for expressing changing by a pattern, for example, Patent Document 2 is known.

  Further, when expressing changing using a pattern, a plurality of images input in advance by an image scanner or the like are required. When expressing moving images by changing, it is necessary to prepare a plurality of images having continuity using computer graphics or the like.

JP 2000-39508 A JP-A-4-136810

  The present invention has been made in view of the above points, and has a high security forgery prevention function that can express a moving image by changing with one original image and is easy to determine authenticity with the naked eye. An object is to provide an image display body and an information medium provided.

According to a first aspect of the present invention, in the image display body in which a plurality of images are formed by disposing a plurality of pixels that emit diffracted light and / or scattered light on one surface of a base material, A plurality of pixels arranged in a matrix on one surface of the substrate, and the pixels can emit diffracted light and / or directional scattered light by illumination light irradiation Each of the pixels constituting each image is configured such that the length directions of the plurality of grooves are the same, and the length directions of the grooves are different between separate images. And the plurality of images are images obtained by representing one original image at different resolutions.
Moreover, 2nd invention is an image display body of Claim 1 in which the said groove | channel is curvilinear.
The third aspect of the present invention is characterized in that the angle range in the tangential direction of the curve of the groove provided in the pixel constituting the separate image is different for each pixel. This is an image display body.
The fourth aspect of the present invention is the image display body according to any one of claims 1 to 3, wherein a plurality of the images have the same center position.
The fifth aspect of the present invention is the image display body according to any one of claims 1 to 4, wherein the plurality of images have the same size.
According to a sixth aspect of the present invention, three or more of the plurality of images are formed, and different images are displayed according to a change in the direction of the plurality of grooves, and the resolution of the images changes with regularity. an image display body according to any one of claims 1 to 5, characterized in that.
According to a seventh aspect of the present invention, three or more of the plurality of images are formed, and different images are displayed according to a change in observation angle, and the images are displayed with regularity in resolution. An image display body according to any one of claims 1 to 5, wherein
The eighth invention is the image display body according to any one of claims 6 and 7, wherein the regularity is an equality number sequence or an equality number sequence.
The ninth invention is the image display body according to any one of claims 1 to 8, wherein the image is an image including personal information.
The tenth invention is an image display body according to claim 9, wherein the image including the personal information is a face image.
An eleventh invention is an information medium comprising the image display body according to any one of claims 1 to 10 and an article that supports the image display body.
According to a twelfth aspect of the present invention, an image including personal information is printed, printed, or displayed in a colored manner on the article, and the original image is the same as the image displayed on the article. The information medium according to claim 11.

According to the present invention, it is possible to provide an image display body and an information medium having a highly secure anti-counterfeit function that can express a moving image by changing with a single original image and that can be easily determined by the naked eye. Is possible.
According to the first aspect of the invention, it is possible to provide an image display body that can be observed like a moving image in which an image is clearly visible or blurred.
According to the second invention, it is possible to provide an image display body in which each image can be observed within a fixed viewing zone width and can be observed like a smoother moving image.
According to the third invention, it is possible to provide an image display body that can be observed like a moving image without generating a viewing zone in which it is difficult to correctly view the image.
According to the fourth aspect of the present invention, it is possible to provide an image display body that makes it possible to observe smoother changing because no image movement in a direction parallel to the image display body occurs.
According to the fifth invention, the movement of the image in the direction perpendicular to the image display body does not occur,
It is possible to provide an image display body that can observe smoother changing.
According to the sixth aspect of the present invention, it is possible to provide an image display body that makes it possible to observe smoother changing.
According to the seventh invention, it is possible to provide an image display body that allows observing smoother changing.
According to the eighth aspect of the invention, it is possible to provide an image display body that can observe smoother changing.
According to the ninth aspect, it is possible to provide an image display body that can be observed as if an image including personal information is a moving image.
According to the tenth invention, it is possible to provide an image display body that can be observed as a moving image including a face image as personal information.
According to the eleventh invention, it is possible to provide an information medium including an image display body that can be observed as a moving image and an article that supports the image display body.
According to the twelfth invention, forgery prevention is further improved by using the same image on an information medium comprising an image display body that can be observed as a moving image and an article that supports the image display body. Is possible.

1 is a plan view schematically showing an information medium according to one embodiment of the present invention. The top view for demonstrating schematically the image display body which concerns on embodiment of this invention. The top view for demonstrating schematically the image display body which concerns on embodiment of this invention. The top view for demonstrating schematically the image display body which concerns on embodiment of this invention. The top view which shows roughly the image display body which concerns on embodiment of this invention. The top view which shows roughly the image display body which concerns on embodiment of this invention. The top view which shows schematically the relationship between an example of the structure employable as a diffraction grating pattern, and the diffracted light emission direction. The top view for demonstrating schematically the image display body which concerns on embodiment of this invention. The top view which shows roughly the image display body which concerns on embodiment of this invention. The top view for demonstrating schematically the image display body which concerns on embodiment of this invention. The top view for demonstrating schematically the image display body which concerns on embodiment of this invention. The top view which shows roughly the structure of a diffraction grating pattern and a light-scattering structure pattern. The top view which shows roughly the information medium which concerns on the other aspect of this invention. The top view which shows roughly the information medium which concerns on the other aspect of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same referential mark is attached | subjected to the component which exhibits the same or similar function through all the drawings, and the overlapping description is abbreviate | omitted.

FIG. 1 is a plan view schematically showing an information medium according to an aspect of the present invention.
An information medium 100 shown in FIG. 1 is a personal authentication medium, and is a booklet such as a passport.
FIG. 1 shows the booklet in an open state.

The information medium 100 includes a signature 1 and a cover 2.
The signature 1 is composed of one or more pieces of paper 11. Typically, an image I2 such as a character string and a background pattern is provided on the piece of paper 11. The signature 1 is formed by folding one paper piece 11 or a bundle of a plurality of paper pieces 11 into two. The paper piece 11 may incorporate an IC (integrated circuit) chip in which personal information is recorded, an antenna that enables non-contact communication with the IC chip, and the like.

  The cover 2 is folded in half. The cover 2 and the signature 1 are overlapped so that the signature 1 is sandwiched by the cover 2 with the booklet closed, and are integrated by binding or the like at the positions of the folds.

  The cover 2 displays an image including personal information. This personal information includes personal authentication information used for personal authentication. This personal information can be classified into, for example, biological information and non-biological personal information.

  The biological information is unique to the individual among the characteristics of the biological body. Typically, biometric information is a feature that can be identified by optical techniques. For example, the biometric information is at least one image or pattern of a face, fingerprint, vein, and iris.

  Non-biological personal information is personal information other than biological information. For example, the non-biological personal information is at least one of name, date of birth, age, blood type, gender, nationality, address, permanent address, telephone number, affiliation, and status. The non-biological personal information may include characters input by typing, may include characters input by machine reading a handwriting such as a signature, or may include both of them. .

In FIG. 1, the cover 2 displays images I1a, I1b, I2 and I3.
The images I1a, I2 and I3 are images displayed using light absorption. Specifically, the images I1a, I2, and I3 are images that are visible when illuminated with white light and observed with the naked eye. One or more of the images I1a, I2 and I3 may be omitted.

  The images I1a, I2 and I3 can be composed of, for example, dyes and pigments. In this case, the images I1a, I2 and I3 can be formed by a thermal transfer recording method using a thermal head, an ink jet recording method, an electrophotographic method, or a combination of two or more thereof. Alternatively, the images I1a, I2 and I3 can be formed by forming a layer containing a thermal color former and drawing on this layer with a laser beam. Alternatively, a combination of these methods can be used. At least a part of the images I2 and I3 may be formed by a thermal transfer recording method using a hot stamp, may be formed by a printing method, or may be formed using a combination thereof.

  The image I1b is an image displayed by the hologram and / or the diffraction grating. The image I1b is formed, for example, by performing thermal transfer recording using a thermal head and thermal transfer recording using a hot stamp or a thermal roll in this order.

  The images I1a and I1b include face images of the same person. The face image included in the image I1a and the face image included in the image I1b may be the same or different. The face image included in the image I1a and the face image included in the image I1b may have the same or different dimensions. Each of the images I1a and I1b may include other biological information instead of the face image, and may further include biological information other than the face image in addition to the face image.

  The image I1b may include non-biological personal information instead of the biological information, and may further include non-biological personal information in addition to the biological information. The image I1b may include non-personal information instead of personal information, and may further include non-personal information in addition to the personal information.

  The image I2 includes non-biological personal information and non-personal information. The image I2 forms, for example, one or more of characters, symbols, codes, and marks.

  The image I3 is a background pattern. For example, the combination of the image I3 and at least one of the images I1a and I1b can make the information medium 100 more difficult to falsify.

  FIG. 2 is a plan view for schematically explaining the image display body according to the embodiment of the present invention. Hereinafter, a description will be given using a diffraction grating pattern as an example of a pixel. However, the present invention is not limited to this, and any structure or function that emits diffracted light and / or scattered light may be provided.

The image display body 10 in FIG. 2A includes a diffraction grating pattern 31a and a non-concave structure region 32.
The diffraction grating pattern 31a includes a plurality of grooves (diffraction gratings).
It is assumed that the diffraction grating angle and the observation direction angle are counterclockwise from the X-axis direction as a positive direction, and the angle is expressed in a range of 0 ° to 180 °. The same applies to the following description. Also, the direction perpendicular to the XY plane is taken as the Z axis, and the direction from the back surface to the front surface is taken as the positive direction of the Z axis.
The angle of the diffraction grating pattern 31a is 0 °. Therefore, since the observation angle 20a is oriented in the direction parallel to the YZ plane, the diffracted light from the diffraction grating pattern 31a can be observed.

The image display body 10 in FIG. 2B includes a diffraction grating pattern 31b and a non-concave structure region 32.
The angle of the diffraction grating pattern 31b is 30 °.
Therefore, since the observation angle 20b is oriented in a direction parallel to a plane including the straight line forming an angle of 120 ° with the X axis and the Z axis, the diffracted light from the diffraction grating pattern 31b can be observed.

The observation angle in the following description is expressed as the angle formed by the vector parallel to the XY plane and the X axis in the XY plane when the observation direction is decomposed into a vector parallel to the XY plane and a vector parallel to the Z-axis direction. And For example, the observation angle 20b in FIG. 2B is 120 °.
In FIG. 2, the pixel is illustrated as a circle, but the shape of the pixel may be a square or a rectangle. In the following drawings, the pixels are illustrated as being circular, but they may be square or rectangular, and are not particularly limited.

The image display body 10 shown in FIG. 2C includes diffraction grating patterns 31a and 31b and a non-relief structure region 32.
The angles of the diffraction grating patterns 31a and 31b are 0 ° and 30 °, respectively.
The observation angle 20a is 90 °, and the observation angle 20b is 120 °.
Therefore, as described in FIGS. 2A and 2B, the diffracted light from the diffraction grating pattern 31a can be observed at the observation angle 20a, and the diffracted light from the diffraction grating pattern 31b can be observed at the observation angle 20b.
That is, when an observer observes the image display body in FIG. 2C, different images can be observed at the observation angles 20a and 20b.
In this way, changing is expressed by configuring individual images with a plurality of diffraction grating patterns having the same direction of the diffraction grating patterns and making the directions of the diffraction grating patterns different between different images. .

  Although not shown this time, as an example of the structure of the diffraction grating pattern, there is a structure in which an uneven structure forming layer, a reflective layer, and a protective layer are sequentially laminated.

  The concavo-convex structure forming layer is a transparent layer in which a plurality of grooves as a diffractive structure are provided on one main surface. As a material for the transparent layer, a resin such as a thermoplastic resin can be used.

  Examples of the material for the concavo-convex structure forming layer include thermoplastic resins such as polyurethane resin, polycarbonate resin, polystyrene resin and polyvinyl chloride resin, unsaturated polyester resin, melamine resin, epoxy resin, urethane acrylate, urethane methacrylate, polyol acrylate, Thermosetting resins such as polyol methacrylate, melamine acrylate, melamine methacrylate, triazine acrylate and triazine methacrylate, mixtures thereof, or thermoformable materials having radically polymerizable unsaturated groups can be used. You may form an uneven | corrugated structure formation layer using resin which has photocurability.

  The reflective layer is formed on the concavo-convex structure forming layer. The reflective layer covers at least a part of the surface of the concavo-convex structure forming layer provided with the plurality of grooves. Although the reflective layer can be omitted, when the reflective layer is provided, the visibility of the image displayed by the plurality of grooves is improved.

  As the reflective layer, a transparent reflective layer or an opaque metal reflective layer can be used. The reflective layer can be formed by, for example, a vacuum film forming method such as vacuum deposition or sputtering. When the reflective layer contains a resin, the reflective layer may be formed by applying or printing.

  When a transparent reflective layer is used as the reflective layer, even when a pattern such as a pattern and characters is arranged on the back side of the reflective layer, it can be visually recognized from the front side of the image display body described later. On the other hand, when an opaque metal reflective layer is used as the reflective layer, it is possible to display an image with high brightness and excellent visibility.

  As the transparent reflective layer, for example, a layer made of a transparent material having a refractive index different from that of the concavo-convex structure forming layer can be used. The transparent reflective layer made of a transparent material may have a single layer structure or a multilayer structure. In the latter case, the transparent reflective layer may be designed so as to repeatedly cause reflection interference. As this transparent material, for example, a transparent dielectric such as zinc sulfide and titanium dioxide can be used.

  Alternatively, a metal layer having a thickness of less than 20 nm may be used as the transparent reflective layer. As a material of the metal layer, for example, a single metal such as chromium, nickel, aluminum, iron, titanium, silver, gold, and copper, or an alloy thereof can be used.

  As the opaque metal reflection layer, the same metal layer as described above for the transparent reflection layer can be used except that it is thicker. The opaque metal reflective layer may be a continuous film. Alternatively, the opaque metal reflective layer may be patterned. For example, at least a part of the opaque metal reflective layer may be patterned to display halftone dots, lines, other graphics, or a combination thereof on the image display body described later. Such a pattern can be used for authenticity determination of the information medium 100, for example.

  A layer containing a transparent resin and particles dispersed therein may be used as the transparent reflective layer or the opaque reflective layer. As the particles, for example, particles made of a metal material such as a single metal and an alloy, or particles made of a transparent dielectric such as a transparent metal oxide and a transparent resin can be used. In the transparent resin, flakes may be dispersed instead of dispersing the particles.

  The protective layer faces the reflective layer with the concavo-convex structure forming layer interposed therebetween. The protective layer has optical transparency and is typically transparent. The protective layer is made of resin, for example. As this resin, for example, an acrylic resin, a urethane resin, or an epoxy resin can be used. The protective layer can be omitted.

  FIG. 3 is a plan view schematically illustrating the image display body according to the embodiment of the present invention.

3A is an image display body 10a having a diffraction grating pattern 31a, FIG. 3B is an image display body 10b having a diffraction grating pattern 31b, and FIG. This is an image display body 10c having a lattice pattern 31c.
3 (d), FIG. 3 (e), and FIG. 3 (f) are the regions Xa provided with the diffraction grating patterns of FIG. 3 (a), FIG. 3 (b), and FIG. A part of Xb and Xc is enlarged.
The angles of the diffraction grating patterns 31a, 31b, and 31c are 0 °, 30 °, and 60 °, respectively. In FIGS. 3A to 3C, different images can be visually recognized, and directions in which the images can be visually recognized are also different.

  FIG. 4 is a plan view for schematically explaining the image display body according to the embodiment of the present invention.

FIG. 4A shows an image display body 10 having a diffraction grating pattern obtained by combining the arrangements of the diffraction grating patterns shown in FIGS. 3A, 3B, and 3C.
FIG. 4B is an example in which a part of the region X provided with the diffraction pattern 11 of FIG.
In the case of FIG. 4B, the diffraction grating patterns 31a, 31b, and 31c are arranged in a stripe shape parallel to the Y axis. Actually, the arrangement of the diffraction grating patterns 31a, 31b, and 31c may be a stripe shape parallel to the X axis as shown in FIG. 4C or a checkered shape as shown in FIG. Rather than a regular arrangement method, random may be used.

When the observer observes the image display body 10 in FIG. 4A, different images can be observed at the observation angles 20a, 20b, and 20c.
In the case of the image display body of FIG. 4A, it is constituted by the diffraction grating patterns shown in FIG. 3A at the observation angle 20a, FIG. 3B at the observation angle 20b, and FIG. 3C at the observation angle 20c. The observed image is observed.
The images observed on the display bodies of FIGS. 3A, 3B, and 3C have a correlation, and the pattern of the image changes continuously.
Therefore, when observing the image display body of FIG. 4A, if the observation angle is moved in the order of 20a, 20b, and 20c, the image can be observed as moving.
The observation angle may be moved in the order of 20c, 20b, and 20a.

  FIG. 5 is a plan view schematically showing an image display body according to the embodiment of the present invention.

5A shows an image display body 10a having a diffraction grating pattern 31a, FIG. 5B shows an image display body 10b having a diffraction grating pattern 31b, and FIG. 5C shows a diffraction pattern. This is an image display body 10c having a lattice pattern 31c.
5 (a), 5 (b), and 5 (c), the images formed by the diffraction grating patterns 31a, 31b, and 31c are 120 cells in both the X and Y directions. It consists of 30 cells and 15 cells. Note that “cell” has the same meaning as “pixel”, and “image pixel” is referred to as “cell” to distinguish it from “diffraction grating pattern pixel”.
5 (d), 5 (e), and 5 (f) are regions Xa provided with the diffraction grating patterns of FIGS. 5 (a), 5 (b), and 5 (c). A part of Xb and Xc is enlarged.
The angles of the diffraction grating patterns 31a, 31b, and 31c are 0 °, 30 °, and 60 °, respectively. In FIGS. 3A to 3C, face images of the same person represented at different resolutions can be viewed, and directions in which the respective images can be viewed are also different.

Note that the resolution in the present invention is the number of cells per unit length. For example, “high resolution” means that the number of cells per unit length is large, and “low resolution” means that the number of cells per unit length is small.
Comparing FIG. 5 (a), FIG. 5 (b), and FIG. 5 (c), it can be said that FIG. 5 (a) has the highest resolution and FIG. 5 (c) has the lowest resolution.

  FIG. 6 is a plan view schematically showing the image display body according to the embodiment of the present invention.

FIG. 6A shows an image display body 10 having a diffraction grating pattern obtained by combining the arrangements of the diffraction grating patterns shown in FIGS. 5A, 5B, and 5C.
FIG. 6B is an enlarged view of a part of the region X provided with the diffraction grating pattern 31 of FIG.
In the case of FIG. 6B, the diffraction grating patterns 31a, 31b, and 31c are arranged in a stripe shape parallel to the Y axis. Actually, the arrangement of the diffraction grating patterns 31a, 31b, and 31c may be a stripe shape parallel to the X axis as shown in FIG. 6C, or a checkered shape as shown in FIG. 6D. Rather than a regular arrangement method, random may be used.

When the observer observes the image display body 10 in FIG. 6A, different images can be observed at the observation angles 20a, 20b, and 20c.
In the case of the image display shown in FIG. 6A, the diffraction grating pattern shown in FIG. 5A is used for the observation angle 20a, FIG. 5B is used for the observation angle 20b, and FIG. The observed image is observed.
The images observed on the respective display bodies of FIGS. 5A, 5B, and 5C have a correlation, and the pattern of the image changes continuously.
Therefore, when observing the image display body of FIG. 6A, if the observation angle is moved in the order of 20a, 20b, and 20c, the image gradually becomes a low resolution and becomes a blurred moving image. Can be observed.
The observation angle may be moved in the order of 20c, 20b, and 20a. In this case, the image can be observed as a moving image that gradually changes to high resolution.

When the image display body 10 shown in FIGS. 4A and 6A is observed, it can be observed that both are moving images as described above. In either case, the visual effect is caused by the fact that the patterns of a plurality of images are continuously changed.
In order to produce the image display body 10 of FIG. 4A, three types of images of FIG. 3A, FIG. 3B, and FIG. 3C are required in advance. These three types of images can be produced using, for example, computer graphics.
In order to produce the image display body 10 of FIG. 6A, three types of images of FIG. 5A, FIG. 5B, and FIG. 5C are required in advance. These three types of images can be produced by outputting a single original image with different resolutions.
That is, in order to produce the image display body 10 of FIG. 4A, image processing by computer graphics is required, while to produce the image display body of FIG. 6A, computer graphics are used. It is only necessary to use one original image without using a complicated system such as a network.
That is, according to the present invention, it is possible to express a moving image by changing by using one original image without going through the troublesome procedure like computer graphics.

  FIG. 7 is a plan view schematically showing an example of a structure that can be employed in the diffraction grating pattern and the relationship between the diffracted light emission directions.

A diffraction grating pattern 31a shown in FIG. 7A is an example of the diffraction grating pattern of the present invention observed from the Z direction. The plurality of grooves of the diffraction grating pattern are straight lines whose length direction is parallel to the same direction (X-axis in this figure), and are arranged at regular intervals in the Y-axis direction. In this case, the diffracted light 22a is emitted in a direction parallel to the Y axis.
A diffraction grating pattern 31d shown in FIG. 7B is an example of the diffraction grating pattern of the present invention observed from the Z direction. The plurality of grooves of the diffraction grating pattern are arranged in a curved line, and are arranged in the same direction at regular intervals in the Y-axis direction. In this case, the diffracted light 22d is emitted with a certain viewing zone width corresponding to the shape of the curve because the grooves of the diffraction grating pattern are curved. In other words, when curved grooves are used instead of linear grooves, the visual effect caused by these grooves can be observed in a wider viewing zone.

  As described above in the description of FIG. 6A and the like, when the observer observes the display body 10 while changing the angle of the display body 10, it can be observed as a moving image due to a changing effect. However, in the case where the diffraction grating pattern has a linear shape as shown in FIG. 7A, for example, when the angle of the display body 10 is changed, the diffracted light is difficult to be observed or an unobservable viewing zone may occur.

  FIG. 8 is a plan view for schematically explaining the image display body according to the embodiment of the present invention.

For example, in the case of FIG. 8, different images can be observed at observation angles 20a and 20b that are perpendicular to the concave and convex directions of the diffraction grating patterns 31a and 31b, but are images not observed at an intermediate position 20d? Or difficult to observe.

  FIG. 9 is a plan view schematically showing the image display body according to the embodiment of the present invention.

FIG. 9A includes diffraction grating patterns 31 e and 31 f and a non-concave structure region 32.
9B and 9C are enlarged views of the diffraction grating patterns 31e and 31f in FIG. 9A, respectively. Here, it is assumed that the diffraction grating patterns 31e and 31f emit diffracted light in an angle range of 90 ° to 120 ° and 120 ° to 150 °, respectively.
FIGS. 9B and 9C are schematic diagrams, and it is not always possible to emit diffracted light in the above-described angle range using the illustrated structure.

The observation angles 20a, 20d, and 20e in FIG. 9A are 90 °, 120 °, and 150 °, respectively.
When the image display body 10 in FIG. 9A is observed while moving the observation angles in the order of 20a, 20d, and 20e, the diffraction grating pattern 31e is observed when the observation angle is 90 ° to 120 °, that is, from the observation angle 20a to the observation angle 20d. Can be observed. When the observation angle is 120 ° to 150 °, that is, the observation angle 20d to the observation angle 20e, an image constituted by the diffraction grating pattern 31f can be observed.
In other words, because the diffraction grating pattern has a curved shape, diffracted light with a certain viewing zone width is emitted, so that the changing effect can be achieved without generating a viewing zone in which diffracted light is difficult to observe or cannot be observed. Can be expressed. Therefore, it can be observed as a more natural and smooth moving image as compared with the case where the diffraction grating pattern is linear.

  FIG. 10 is a plan view for schematically explaining the image display body according to the embodiment of the present invention.

FIG. 10A includes diffraction grating patterns 31 g and 31 h and a non-concave structure region 32.
10 (b) and 10 (c) are enlarged views of the diffraction grating patterns 31g and 31h in FIG. 10 (a), respectively. Here, it is assumed that the diffraction grating patterns 31g and 31h emit diffracted light in an angle range of 90 ° to 135 ° and 120 ° to 165 °, respectively.
FIGS. 10B and 10C are schematic diagrams, and it is not always possible to emit diffracted light within the above-described angle range using the illustrated structure.

The observation angles 20a, 20d, 20g, and 20h in FIG. 10A are assumed to be 90 °, 120 °, 135 °, and 165 °, respectively.
When the image display body 10 shown in FIG. 10A is observed while moving the observation angles in the order of 20a, 20d, 20g, and 20h, the diffraction grating is observed when the observation angle is 90 ° to 135 °, that is, from the observation angle 20a to the observation angle 20g. An image composed of the pattern 31g can be observed, and an image composed of the diffraction grating pattern 31h can be observed when the observation angle is 120 ° to 165 °, that is, from the observation angle 20d to the observation angle 20h.
In this case, when the observation angle is 120 ° to 135 °, that is, from the observation angle 20d to the observation angle 20g, both the image constituted by the diffraction grating pattern 31g and the image constituted by the diffraction grating pattern 31h are observed simultaneously. Thus, it becomes difficult to correctly view the observed image.

On the other hand, in the case of FIG. 9 described above, images formed by the diffraction grating patterns 31e and 31f are not observed at the same time or are unlikely to occur.
That is, when the diffraction grating pattern has a curved shape and there is an overlap in the range of diffracted light emission angles of different diffraction grating patterns, there is a possibility that an observation angle that makes it difficult to visually recognize an image may occur.
Therefore, according to the present invention, when the diffraction grating pattern has a curved shape, the angle range in the tangential direction of the curve of the groove is set to be different between pixels of each image. For example, by not overlapping the tangential angle ranges of the diffraction grating patterns that make up separate images, it is possible to express a moving image without causing an observation angle that makes it difficult to correctly view the image. Is possible. In addition, when the respective angle ranges are adjacent to each other, it is possible to view the images continuously without interruption.

  FIG. 11 is a plan view for schematically explaining the image display body according to the embodiment of the present invention.

The images in FIGS. 11A, 11B, and 11C are images of 120 cells, 60 cells, and 30 cells in both the X direction and the Y direction, respectively.
When the images are observed in the order of FIG. 11A, FIG. 11B, and FIG. 11C due to the changing effect, the image gradually changes to a lower resolution and thus appears blurred. In the case of FIG. 11, how to change the number of cells of an image can be represented by a geometric sequence. In this case, it can be observed as a smoother moving image as compared with a case where the manner of changing the number of cells of the image is irregular. The method of changing the number of cells is not limited to the geometric progression, but may be an arithmetic progression. It is not limited to the geometric sequence and the equidistant sequence, and if it has a certain regularity, it can be observed as a smoother moving image as compared with the case where there is no regularity. 11 (a), 11 (b), and 11 (c), and the case of changing in the images of FIGS. 5 (a), 5 (b), and 5 (c). In the case of FIG. 5, since the amount of change in the number of cells of the image is larger, it can be observed as changing where the resolution changes more rapidly. That is, it is possible to control the degree of image change due to the changing effect by changing the number of cells.

The center positions of the images in FIGS. 11A, 11B, and 11C are the same.
Therefore, when the images are observed in the order of FIG. 11A, FIG. 11B, and FIG. 11C due to the changing effect, it is a moving image in which only the resolution is changed without changing the position of the image. Can be observed.
In other words, by making the center positions of the images the same, it can be observed as a moving image that does not move in the XY directions, so that the changing effect that changes the resolution can be more easily observed.

The images shown in FIGS. 11A, 11B, and 11C have the same size.
Therefore, when images are observed in the order of FIGS. 11A, 11B, and 11C due to the changing effect, the images are not observed as moving images that move in the Z direction.
That is, by making the image size the same, it can be observed as a moving image that does not move in the Z direction, so that the changing effect that changes the resolution can be more easily observed.

  FIG. 12 is a plan view schematically showing the structure of the diffraction grating pattern and the light scattering structure pattern.

  FIG. 12A is a plan view schematically showing the structure of the diffraction grating. Black and white are alternately drawn at equal intervals, which indicates a structure in which the irregularities of the diffraction grating are regularly repeated.

FIG. 12B is a plan view schematically showing the light scattering structure pattern. Similar to FIG. 7A, the concave and convex grooves are indicated by black and white. Compared to FIG. 12A, the length direction is the same, but the groove spacing is irregular. This irregularity makes it possible to emit scattered light. However, although FIG. 12B shows an irregular structure, all the structures are along the X-axis direction. Therefore, in FIG. 12A, scattered light is emitted in the Y-axis direction, so that diffracted light is emitted in the Y-axis direction.
1 to 10, the light scattering structure pattern as illustrated in FIG. 12B may be used instead of the diffraction grating pattern.

The information medium 100 as a passport has been exemplified above, but the technology described above for the information medium 100 can be applied to other information media. For example, this technique can be applied to various cards such as a visa and an ID card.

FIG. 13 is a plan view schematically showing an information medium according to another aspect of the present invention.
The information medium 200 is a magnetic card and includes a base material 51. The base material 51 is made of plastic, for example. A printed layer 52 and a strip-shaped magnetic recording layer 53 are formed on the substrate 51. Furthermore, the image display body 10 is affixed on the base material 51 as an anti-counterfeit or personal identification label.

  The information medium 200 includes the display body 10. Therefore, forgery or imitation of this information medium 200 is difficult.

FIG. 14 is a plan view schematically showing an information medium according to another aspect of the present invention. An information medium 300 shown in FIG. 14 is an ID card, and includes an image I1b based on the image display body 10 described above. Therefore, this information medium 300 is difficult to tamper with.

The material of the base material to which the image display body is attached may not be paper such as natural paper and synthetic paper. For example, the material of the base material to which the image display body 300 is attached is a polyethylene terephthalate resin (thermoplastic PET), a polyvinyl chloride resin, a thermosetting polyester resin, a polycarbonate resin, a synthetic resin such as a polymethacrylic resin and a polystyrene resin, or glass. It may be ceramics such as ceramics and porcelain, or metal materials such as simple metals and alloys.

In the above, personal authentication media such as passports and ID cards have been exemplified as information media.
The technology described above for the information media 100 and 300 can also be applied to information media other than personal authentication media. That is, the technique described above may be used for purposes other than personal authentication, such as individual authentication.

  The pixel is a 42 μm square. The pixel is composed of a curved diffraction grating pattern, and four types of diffraction grating patterns are used. The diffraction light exit angles of the four types of diffraction grating patterns are 67.12 ° to 78.56 °, 78.56 ° to 90.00 °, 90.00 ° to 101.44 °, 101.44 ° to 112, respectively. Suppose that it is 88 °.

  Assume that four types of diffraction grating patterns use one face image as an original image and four types of face images having different numbers of cells. The image sizes are all the same, and the ratio of the lengths in the X and Y directions is 5: 6. The number of cells in the X direction of the image is 150, 50, 25, and 12.5, respectively. Further, it is assumed that the center positions of the images are the same.

  As a result, when the display body of this example was observed while changing the observation angle, the resolution was changed, so that the face image could be observed as a moving image that looked clear or blurred.

DESCRIPTION OF SYMBOLS 1 ... Signature 2 ... Cover 10, 10a, 10b, 10c ... Image display body 11 ... Paper piece 14, I1a, I1b, I2, I3 ... Image 20a, 20b, 20c, 20d, 20e ... Observation angle 21 ... Light source 22a, 22d ... Diffraction light emission direction 31, 31a, 31b, 31c, 31d, 31e, 31f, 31g, 31h ... Diffraction grating pattern 32 ... Non-concave structure region 51 ... Base material 52 ... Print layer 53 ... Magnetic recording layers 100, 200, 300 ... Information media X, Xa, Xb, Xc ... area

Claims (12)

In the image display body in which a plurality of images are formed by arranging a plurality of pixels that emit diffracted light and / or scattered light on one surface of the substrate,
Having a light transmissive substrate,
A plurality of pixels arranged in a matrix on one surface of the substrate,
The pixel is
It has a plurality of grooves that can emit diffracted light and / or scattered light having directivity by irradiation of illumination light,
Each pixel constituting an individual image is configured such that the length direction of the plurality of grooves is the same direction,
The length direction of the groove is different between separate images,
The plurality of images are images obtained by representing one original image at different resolutions.   The image display body according to claim 1, wherein the groove has a curved shape.   The image display body according to claim 2, wherein an angle range in a tangential direction of a curve included in the groove included in the pixel constituting the separate image is different for each pixel.   The image display body according to claim 1, wherein center positions of the plurality of images are the same.   The image display body according to claim 1, wherein the plurality of images have the same size. Three or more of the plurality of images are formed,
Displaying different images according to changes in the direction of the plurality of grooves,
The image, the image display body according to any one of claims 1 to 5, characterized in that the resolution is changed with regularity. Three or more of the plurality of images are formed,
Display different images according to changes in observation angle,
6. The image display body according to claim 1, wherein the image is displayed with regularity in resolution.   The image display body according to claim 6, wherein the regularity is an equality number sequence or an equality number sequence.   The image display body according to claim 1, wherein the image is an image including personal information.   The image display body according to claim 9, wherein the image including the personal information is a face image.   An information medium comprising: the image display body according to claim 1; and an article that supports the image display body. An image including personal information is printed, printed, or displayed in a colored manner in the article,
The information medium according to claim 11, wherein the original image is the same as an image displayed on the article.