JPH0688905A - Method to prevent forgery of diffraction grating pattern, and recording medium having diffraction grating pattern to prevent forgery - Google Patents

Abstract

PURPOSE:To provide a method to prevent forgery of diffraction grating pattern in which specified information is recorded, and to provide a recording medium of diffraction grating pattern protected from forgery. CONSTITUTION:Patterns 21-24 to be recorded are recorded with diffraction gratings or interferencial fringes in a specified direction and at specified intervals formed in the respective pattern regions. Each pattern area is surrounded with several pattern areas of diffractor gratings or interferencial fringes different in at least interval or direction of gratings or fringes from that of the recording pattern area. Thus, forgery of the recorded diffraction grating pattern 1 can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing the same thing from being forged when a pattern such as a character or a pattern is recorded according to the position, arrangement or shape of a diffraction grating or a region where interference fringes are formed. The present invention relates to a diffraction grating pattern or interference fringe pattern recording body with such forgery prevention.

[0002]

2. Description of the Related Art Conventionally, it is well known in calendars, bar codes, etc. to record and display patterns such as characters and patterns by the contour of the area where diffraction gratings or interference fringes are formed.
Hereinafter, such a pattern is referred to as a diffraction grating pattern.

It is also well known to form anti-counterfeit information on a card or the like with such a diffraction grating pattern.

[0004]

By the way, such a diffraction grating pattern is usually easily readable by visual observation, and it is not always difficult to read and forge it.

The present invention has been made in view of such circumstances, and an object thereof is to provide a method for preventing forgery of a diffraction grating pattern in which specific information is recorded, and a diffraction grating pattern recording body in which such forgery is prevented. Is to provide.

[0006]

The diffraction grating pattern forgery prevention method of the present invention which achieves the above-mentioned object, is one in which a pattern to be recorded is formed in a region including at least the pattern region, or a plurality of different types are specified. Recording with diffraction gratings or interference fringes of directions and intervals, or with a plurality of different types of diffraction gratings or interference fringes of specific directions and intervals that are parallel or superposed, and at least around the direction of the gratings or stripes It is characterized in that one of them is formed so as to be surrounded by a diffraction grating or an interference fringe area different in direction or spacing of the grating or fringes of the recording pattern area, thereby preventing forgery of the recorded diffraction grating pattern. Is the way.

The present invention also provides a pattern to be recorded,
At least one kind or different kinds of diffraction gratings or interference fringes formed in an area including the pattern area, or a plurality of different kinds of parallel or superposed diffraction gratings of specific directions and distances, or Recording is performed by interference fringes, and at least one of the orientations of the gratings or fringes and the spacing thereof is surrounded by a diffraction grating or an area of interference fringes in which one of the orientations of the gratings or fringes of the recording pattern area or the spacing is different. The present invention includes a diffraction grating pattern recording method characterized by recording a grating pattern.

Further, according to the present invention, the pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having specific directions and intervals formed in an area including at least the pattern area, or in parallel or superposition. Recording is performed by a plurality of different types of diffraction gratings or interference fringes having specific directions and intervals, and at least one of the orientations of the gratings or fringes and the spacing is different from the orientations or intervals of the lattices or fringes of the recording pattern area. Diffraction grating pattern recorded by being surrounded by a diffraction grating or an interference fringe area is irradiated with illumination light from a predetermined direction, and diffracted light diffracted in a specific direction from the illumination position is read to obtain a diffraction grating pattern. It can also be used as a method of reading a recording medium.

Further, according to the present invention, the pattern to be recorded is
At least one kind or different kinds of diffraction gratings or interference fringes formed in an area including the pattern area, or a plurality of different kinds of parallel or superposed diffraction gratings of specific directions and distances, or Diffraction gratings recorded by interference fringes and surrounded by a diffraction grating or a region of interference fringes in which at least one of the direction of the gratings or fringes and the interval is different from the direction of the gratings or fringes of the recording pattern region, or the interval. By applying illumination light to the pattern recording medium from a predetermined direction and detecting the diffracted light diffracted in a specific direction from the illumination position, it can be used as a method for determining the authenticity of the diffraction grating pattern recording medium.

Further, the anti-counterfeiting diffraction grating pattern recording body of the present invention is a diffraction grating or interference of a pattern to be recorded, which is formed in an area including at least the pattern area, of one kind or a plurality of different kinds in specific directions and intervals. Recording is performed by stripes, or by a plurality of different types of diffraction gratings or interference fringes that are parallel or overlapped and have different specific directions and intervals, and at least one of the direction of the stripes or the stripes and the interval is the grating of the recording pattern area. Alternatively, it is characterized by being recorded by being surrounded by a diffraction grating or an interference fringe region having a different fringe direction and spacing.

In this case, the recording pattern area can be formed as a bar code pattern, or the recording body can be formed on the entire surface or a part of the card. Further, this recording body can be formed in a portion where a punch hole of a card is provided and can be used for preventing forgery and tampering.

The anti-counterfeit diffraction grating pattern recording material of the present invention can be formed as a transfer foil.

[0013]

According to the present invention, the pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having a specific direction and spacing formed in an area including at least the pattern area, or in parallel or in superposition. Recorded by diffraction gratings or interference fringes of a plurality of different specific directions and intervals, around which at least the orientation of the gratings or fringes,
Since one of the intervals is surrounded by a direction of the grating or fringes of the recording pattern area, a diffraction grating or an interference fringe area different from the interval to form a diffraction grating pattern recording body, which area is recorded by a glance at a glance. It is not known whether it is the information area, and when the area is mechanically read by the diffracted light from the diffraction grating or interference fringes of the recording pattern area, the light diffracted in which direction is from the recording pattern. Alternatively, it cannot be determined unless the position of the recording pattern area and the direction and spacing of the grid or stripe are known in advance.
Therefore, a diffraction grating pattern recording body that is difficult to forge is obtained.

[0014]

Embodiments of the diffraction grating pattern forgery prevention method and the forgery prevention diffraction grating pattern recording body of the present invention will be described below with reference to the drawings. In the following description, information is recorded by a diffraction grating, but a hologram having substantially parallel interference fringes may be used instead of the diffraction grating.

[0015] Figure 1 is a 1 as an example, a plan view of a diffraction grating pattern recording body 1 a bar code was recorded by the contour of the diffraction grating formation portion of the present invention, in the figure, reference numeral 2 ₁ to 2
_{The four} horizontal diffraction grating regions shown by 4 represent the barcode. A pattern these areas for recording original information, Around the orientation of at least the grating, a large number of diffraction grating areas while intervals different from that of the recording pattern area ₂₁ to ₂₄ (dummy diffraction grating) is surrounded As is clear from the figure, it is not possible to know which area is the recorded information area by a glance because it is camouflaged. Further, as will be described later, even when mechanically reading by the diffracted light from these diffraction gratings,
It cannot be determined in which direction the light diffracted is from the recorded information area unless the direction and interval of the diffraction gratings of the recording pattern areas 2 ₁ to 2 ₄ are known in advance. Therefore, it is possible to form a bar code that is difficult to forge. Incidentally, in the case of FIG. 1, the recording pattern area 2 ₁ -
This is an example of recording 2 ₄ with one kind of diffraction grating, but as shown in FIG. 2, the grating patterns 2 ₁ to 2 ₄ are recorded by the combination of the horizontally oriented grating a and the relatively coarse left downward grating b. You can also do it. Further, instead of arranging two grids in parallel, a pattern is formed by multiple recording, or the recording pattern area is further divided into minute areas,
You may make it arrange | position a lattice of more than 1 type (for example, Unexamined-Japanese-Patent No. 3-211096, Japanese Patent Application No. 3-303413-4.
No.). Furthermore, a horizontally oriented grating a and a relatively coarse leftwardly descending grating b may be provided independently, and grating patterns 2 ₁ to 2 ₄ which are patterns to be recorded by a and b may be recorded. . Of course, also in these cases, it is difficult to forge by surrounding them with a dummy diffraction grating.

Further, in the case of FIG. 3, a diffraction grating region oriented in the horizontal direction is formed in a region including the recording slip patterns 2 ₁ to 2 ₄ regions. A relatively coarse left-down diffraction grating (dummy diffraction grating) is formed around this region. By forming a diffraction grating in a region including a pattern to be recorded in this way, it becomes difficult to understand the existence of the pattern itself, and even if only one type of dummy diffraction grating is provided, it is difficult to forge. Become. Such a diffraction grating pattern recording body 1 can be manufactured by only exposing twice using a mask pattern.

By the way, there are several possible methods for reading a diffraction grating pattern that is difficult to forge formed by surrounding the dummy diffraction grating in this way. The first method is to illuminate with a monochromatic beam from a predetermined direction. while moving the diffraction grating pattern recording body 1, the illumination area so as to traverse recording medium 1, by disposing a light receiving element in a specific direction for receiving the diffracted light from the grating pattern ₂₁ to _24, as a temporal signal This is a method of reading a recording pattern. FIG. 4 schematically shows an arrangement for reading the card 3 in which the recording body 1 on which the barcode is recorded as shown in FIG. 1 is attached to the stripe area 4. When the card 3 is moved in the direction of the arrow while the beam light from the monochromatic light source 5 such as a semiconductor laser is applied to the stripe region 4, the illumination light is diffracted from the regions 2 ₁ to 2 _{4 in a} specific direction and arranged at that position. It is incident on the received light receiving element 6.
Of course, the illuminating light is diffracted from the dummy diffraction grating around it, as described above, the orientation of their grating, the spacing is different from that of the region ₂₁ to _24, the illumination light illuminates the dummy diffraction grating Light does not enter the light-receiving element 6 at the position. Therefore, with the movement of the card 3, a signal having a waveform as shown in FIG. 5, for example, is obtained from the light receiving element 6, the recorded bar code can be read from this signal, and the recording medium is It is also possible to judge whether it is a true one or a forged one. As another reading method, when the recording medium 1 is irradiated with illumination light having an illumination region that covers the entire recording medium 1 from a predetermined direction, only the recording pattern region diffracts the illumination light in a specific direction. If a CCD camera or the like is installed in the specific direction, the diffracted light can be easily recognized. It goes without saying that instead of the CCD camera or the like, it is possible to visually determine whether the image is forged. In addition, as shown in FIG. 2, in order to read a diffraction grating pattern formed by using a plurality of diffraction gratings, such as arranging a plurality of diffraction gratings in parallel, it is necessary to set the diffraction light from each diffraction grating at a position in the direction of receiving light. A plurality of corresponding light receiving elements are arranged, and the signals obtained from the respective light receiving elements are added (in the case of parallel) or multiplied (in the case of superposition) to read the barcode and determine whether the signal is true or false. Further, when the diffraction grating pattern is recorded as a two-dimensional pattern, reading may be performed by causing the above-mentioned illumination area to scan the recording medium two-dimensionally.

Next, as another method of reading a diffraction grating pattern that is difficult to forge formed by surrounding it with a dummy diffraction grating as shown in FIGS. 1 and 2, there is a method of using spatial filtering. One example is shown in the optical path diagram of FIG. The recording body 1 is arranged at the front focal point of the lens L1, and the spatial filter F is arranged at the rear focal plane thereof. Further, the lens L2 is arranged coaxially with the spatial filter F as the front focal plane, and the screen or the two-dimensional light receiving element S is arranged on the rear focal plane of the lens L2. When the recording body 1 is illuminated with the coherent monochromatic light 7 along the optical axis in such an arrangement, the 0th order light 8 is condensed at the center of the spatial filter F by the lens L1. Also, the recording body 1
The diffracted light 9 from the pattern area 2 including the information of (1) is condensed by the lens L1 on the spatial filter F at a position corresponding to the spatial frequency of the diffraction grating. When the hole 10 is provided at this position of the spatial filter F, only the diffracted light 9 from the pattern region 2 passes through the spatial filter F, and the lens L2 makes it similar to the pattern region 2 on the screen or the two-dimensional light receiving element S. Since the patterns 2'are connected, the pattern area 2 of the recording body 1 can be read. Since the diffracted light from the dummy diffraction grating is condensed at a position different from the hole 10 of the spatial filter F and blocked by the spatial filter F, only the diffraction grating pattern 2 including information is on the screen or the two-dimensional light receiving element S. Can be obtained.

The recording medium as described above can be used, for example, as a recording portion for preventing forgery of cards such as prepaid cards and CD cards. In that case, as shown in FIG. 4, the recording medium of the present invention is provided in the stripe area 4 or a specific part of the card 3 so that the required information which is difficult to forge is recorded. Further, particularly in a card such as a prepaid card that records and displays the usage frequency by punching holes, as shown in the plan view of FIG.
A diffraction grating pattern according to the present invention is provided in a portion 11 of the punched hole opening portion of the card 3 so that required information can be read before the card is used and the card 3 is prevented from being tampered with again after use. You can also

The above diffraction grating pattern recording medium may be directly recorded on a recording medium such as a card, but it is constructed as a diffraction grating pattern transfer foil and is transferred to the recording medium. It is realistic to use it. FIG. 8 is a cross-sectional view of an embodiment in which such a diffraction grating pattern is formed as a reflection relief diffraction grating and is formed on a transfer foil. The reflection relief diffraction grating pattern is a diffraction grating layer 12 and an uneven grating or interference on the surface thereof. The reflective layer 13 is formed on the striped surface (relief surface), and the reflective layer 13 may be formed of a vapor-deposited metal film of aluminum, tin or the like, or may be formed of a high refractive index transparent film of zinc sulfide or the like. When it is made of a vapor-deposited metal film, it has a reflection type relief diffraction grating pattern that reflects incident light almost completely by the metal. However, when it is made of a high refractive index transparent material film, it is between the diffraction grating layer 12 and the reflection layer 13. Because of Fresnel reflection based on the difference in refractive index,
It becomes a reflection type relief diffraction grating pattern of a type that reflects a part of incident light. As a method of manufacturing such a reflection type relief diffraction grating pattern, after recording the diffraction grating pattern as a concave and convex pattern on a photoresist or the like, this concave and convex pattern is molded by plating or the like, and this mold is used for the diffraction grating layer 12 The transparent resin layer forming the layer is imprinted and duplicated, and the reflective layer 13 is formed on the duplicated concavo-convex pattern by vapor deposition or the like. A method in which a reflective layer 13 is formed on a resin layer, and a mold having the above-mentioned concavo-convex pattern formed on the reflective layer 13 is heated and pressed to make a duplicate (for example, JP-A-58-58). 65466). In order to transfer such a relief diffraction grating pattern, PET (polyethylene terephthalate)
A transparent resin layer forming the diffraction grating layer 12 is provided on the base film 15 made of, for example, and the reflection layer 13 is formed after patterning the concavo-convex pattern, or the reflection layer 13 is formed.
After forming, the concave-convex pattern is molded, and the heat-sensitive adhesive layer 16 made of a resin having a low melting point is provided on the reflective layer 13. In order to transfer the diffraction grating layer 12 and the reflection layer 13 in the desired contour area portion of the transfer foil having such a structure onto a card substrate made of vinyl chloride, for example, by using a heating die,
As shown in FIG. 9, the transfer foil is set so that the heat-sensitive adhesive layer 16 faces the substrate 3 between the card substrate 3 and the heating die 17 to be transferred, and the base film 15 opposes the heating die 17. The heating mold 17 may be driven. A thermal head may be used instead of the heating die.

The forgery prevention method and the recording medium of the present invention have been described above based on some embodiments, but the present invention is not limited to these embodiments and various modifications can be made.

[0022]

As described above, according to the anti-counterfeiting diffraction grating pattern and the anti-counterfeiting diffraction grating pattern recording body of the present invention, the pattern to be recorded is a type formed in at least the area including the pattern area or Recording is performed by different plural kinds of diffraction gratings or interference fringes having specific directions and intervals, or by plural different kinds of diffraction gratings or interference fringes having different specific directions and distances, which are parallel or superposed.
Camouflage because a diffraction grating pattern recording medium is formed by surrounding it with a diffraction grating or interference fringe area in which at least one of the orientation of the grating or the stripe and the spacing of the grating or stripe of the recording pattern area or the spacing is different. And at first glance it is not possible to know which area is the recorded information area, and also when reading that area mechanically with diffracted light from the diffraction grating or interference fringes of the recording pattern area,
It cannot be determined in which direction the light diffracted is from the recording pattern unless the position of the recording pattern area and the direction and interval of the grating or stripes are known in advance. Therefore, a diffraction grating pattern recording body that is difficult to forge is obtained.

[Brief description of drawings]

FIG. 1 is 1 of an anti-counterfeiting diffraction grating pattern recording body of the present invention.
It is a top view of an example.

FIG. 2 is a plan view of another embodiment.

FIG. 3 is a plan view of another embodiment.

FIG. 4 is a schematic view showing one arrangement for reading a barcode recording medium according to the present invention.

5 is a waveform diagram of a signal obtained in the case of FIG.

FIG. 6 is an optical path diagram showing another arrangement for reading.

FIG. 7 is a plan view of an embodiment in which a recording medium according to the present invention is formed in a punch hole portion of a card.

FIG. 8 is a cross-sectional view in the case where the recording material according to the present invention is formed as a transfer foil.

9 is a diagram for explaining a method of transferring the transfer foil of FIG. 8 to a card.

[Explanation of symbols]

1 ... diffraction grating pattern recording body ₂₁ to ₂₄ ... barcode diffraction grating region a ... first diffraction grating region b ... second in parallel diffraction grating region 3 ... card 4 ... stripe regions 5 ... monochromatic light source 6 in parallel ... Light receiving element 7 ... Coherent monochromatic light L1, L2 ... Lens F ... Spatial filter S ... Screen or two-dimensional light receiving element 8 ... 0th-order light 9 ... Diffracted light 10 ... Spatial filter hole 11 ... Punch hole planned opening portion 12 ... Diffraction grating layer 13 ... Reflective layer 14 ... Release layer 15 ... Base film 16 ... Heat-sensitive adhesive layer 17 ... Heating mold

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G06K 19/06 G09C 5/00 8837-5L

Claims (9)

[Claims] 1. A pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having specific directions and intervals formed in a region including at least the pattern region, or a plurality of different patterns arranged in parallel or superposed. Recorded by a diffraction grating or interference fringes of a specific direction and spacing of the species,
A recorded diffraction grating pattern is formed by surrounding it with a diffraction grating or an interference fringe area in which at least one of the orientation of the grating or the stripe and the spacing of the grating or stripe of the recording pattern area is different from the orientation or the interval of the recording pattern area. A method for preventing forgery of a diffraction grating pattern, characterized in that the counterfeiting is prevented. 2. The pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having a specific direction and spacing formed in an area including at least the pattern area, or by a plurality of different parallel or superposed patterns. Recorded by a diffraction grating or interference fringes of a specific direction and spacing of the species,
Recording a diffraction grating pattern by surrounding and forming a diffraction grating or an interference fringe area in which at least one of the orientation of the grating or the stripe and the spacing of the recording pattern area is different from the orientation of the grating or the stripe or the spacing. And a diffraction grating pattern recording method. 3. A pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having a specific direction and spacing formed in an area including at least the pattern area, or a plurality of different patterns arranged in parallel or superposed. Recorded by a diffraction grating or interference fringes of a specific direction and spacing of the species,
Around this, at least one of the direction of the grating or the stripe and the interval of one of the intervals of the grating or the stripe of the recording pattern area is different from the direction of the grating or the stripe, and the diffraction grating pattern recorded on the recording medium is surrounded by the area of the interference fringes. A method of reading a diffraction grating pattern recording medium by applying illumination light from a direction and reading diffracted light diffracted in a specific direction from an illumination position. 4. A pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having a specific direction and interval formed in an area including at least the pattern area, or a plurality of different parallel or superposed patterns. Recorded by a diffraction grating or interference fringes of a specific direction and spacing of the species,
Around this, at least one of the direction of the grating or the stripe and the interval of one of the intervals of the grating or the stripe of the recording pattern area is different from the direction of the grating or the stripe, and the diffraction grating pattern recorded on the recording medium is surrounded by the area of the interference fringes. A method of determining the authenticity of a diffraction grating pattern recording body by applying illumination light from a direction and detecting diffracted light diffracted in a specific direction from an illumination position. 5. A pattern to be recorded is formed by one or a plurality of different types of diffraction gratings or interference fringes having specific directions and intervals formed in an area including at least the pattern area, or a plurality of different patterns arranged in parallel or superposed. Recorded by a diffraction grating or interference fringes of a specific direction and spacing of the species,
Anti-counterfeiting diffraction, characterized in that at least one of the direction of the grating or the stripes and one of the intervals is surrounded and recorded by a diffraction grating or a region of interference fringes different from the direction of the grating or the stripes of the recording pattern area, or the interval. Lattice pattern recording body. 6. The anti-counterfeit diffraction grating pattern recording body according to claim 5, wherein the recording pattern area is a bar code pattern. 7. The anti-counterfeit diffraction grating pattern recording body according to claim 5, wherein the recording body is formed on the entire surface or a part of the card. 8. The recording medium is formed in a portion of a card where a punch hole is provided.
An anti-counterfeit diffraction grating pattern recording body according to any one of 1. 9. The anti-counterfeit diffraction grating pattern recording body according to claim 5 or 6, which is formed as a transfer foil.