JP2001307015A - Card authenticity deciding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a card authenticity deciding device capable of objectively and exactly deciding the authenticity of a card provided with a hologram image formed by a diffractive pattern on its surface. SOLUTION: The card authenticity deciding device is provided with a projection system 10 to project a laser measurement light flux Q1 to the hologram image 4 provided on the surface of the card 1 and formed by the diffractive pattern 3, a light reception system 20 having a Fourier transformation lens 21 to form the image of the diffractive pattern on a line sensor 22 by a diffractive reflection light flux Q2 reflected from the hologram image 4 and a deciding part 32 to decide the authenticity of the hologram image 4 based on a signal from the line sensor 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a card authenticity judging device for judging the authenticity of a card provided with a hologram on which an image based on a diffraction pattern is formed.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 7A, a card 1 such as a credit card has a hologram sticker 2 attached to the surface thereof.

[0003] The hologram seal 2 has a structure shown in FIG.
As shown in FIG. 4 (partially enlarged), a hologram image 4 imitating a pattern, mark, character, etc. formed from the diffraction pattern 3.
Are formed.

In general, the hologram image 4 is employed in the above-described credit card and the like because the appearance of the card 1 is improved and at the same time, it is difficult to disguise the card.

[0005] On the other hand, such a hologram image 4 can be obtained by visually observing the hologram image 4 itself or by using an optical device to determine the partial shape (including the entire shape) and the position where the card 1 is attached. I was making a false judgment.

[0006]

However, in order to determine the authenticity of the card 1 with the naked eye, since the image changes depending on the delicate direction of the incident light beam, it is difficult to perform strict authenticity determination. There was a problem of difficulty.

[0007] When the authenticity of the partial shape (including the entire shape) and the position where the card 1 is stuck is determined using an optical device, it is difficult to disguise the hologram image 4. There has been a problem that it is relatively easy to restore the shape and the attachment position, and it is difficult to make a strict true / false determination.

Therefore, focusing on the fact that the depth and pitch of the grooves of the diffraction pattern 3 of the hologram image 4 are strictly controlled, it is necessary to analyze the hologram image 4 for a part or a minimum part which is not an element of the overall shape. Has led to the idea that strict judgments can be made objectively.

The present invention, in order to solve the above-mentioned problem, provides a card authenticity determination apparatus capable of objectively and strictly determining the authenticity of a card provided with a hologram image formed by a diffraction pattern on a surface. The purpose is to:

[0010]

In order to achieve the object, a card authenticity determination device according to claim 1 is provided with a laser measurement light beam toward a hologram image provided on a card surface and formed by a diffraction pattern. A projection system for projecting, a light receiving system having a Fourier transform lens for forming a diffraction pattern image on the light receiving portion by a diffracted and reflected light beam reflected from the hologram image, and authenticating the hologram image based on a signal from the light receiving portion. The gist of the present invention is to include a determination unit for determining.

According to a second aspect of the present invention, there is provided a card authenticity determination apparatus,
The gist is that the determination unit includes a display unit that displays the determination result.

According to a third aspect of the present invention, there is provided a card authenticity determination apparatus,
The gist is that the judgment unit judges the authenticity of the hologram image based on the analysis result from the analysis unit for analyzing the diffraction pattern image.

According to a fourth aspect of the present invention, there is provided a card authenticity determination apparatus,
The analysis unit analyzes the formation position, peak intensity, and spread width of the diffraction pattern image and outputs the analysis result to the determination unit.

According to a fifth aspect of the present invention, there is provided a card authenticity determination apparatus,
The determination unit, when determining that all of the diffraction pattern image formation position, peak intensity, and spread width are genuine, determines that the card is a genuine card and informs the display unit that the card is a genuine card. The gist is to display it.

According to a sixth aspect of the present invention, there is provided a card authenticity determination device,
The determining unit, when determining that any one or more of the formation position, the peak intensity, and the spread width of the diffraction pattern image is a fake, determines that the card is a fake card, and informs that the card is a fake card. The gist of the present invention is to display on the display unit.

According to a seventh aspect of the present invention, there is provided a card authenticity determination device,
The determination unit determines that the card is a genuine card when it is determined that all of the formation position, the peak intensity, and the spread width of the diffraction pattern image are genuine, and only one of the genuine cards is subjected to a predetermined analysis. If it is determined to be a pseudo card within the range, it is determined that the card is a temporary genuine card, and if it is determined that at least one of the cards is a fake card, it is determined that the card is a pseudo card, and the result of the determination is determined. The gist of the present invention is to display on the display unit.

[0017] The card authenticity determination device according to claim 8 is
The gist is that, when a plurality of types of pitches or directions of the diffraction pattern exist, the determination unit makes a determination based on an analysis result for one or all of the types.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a card authenticity judging device according to the present invention will be described with reference to FIGS.

1A and 1B, reference numeral 10 denotes a projection system for projecting a laser measurement light beam Q1 toward a hologram seal 2 provided on the surface of the card 1, and reference numeral 20 denotes a diffraction reflection reflected from the hologram 2. A light receiving system for receiving the light flux Q2,
Reference numeral 30 denotes an analysis / determination unit that analyzes and determines the authenticity of the card 1 based on the diffracted reflected light beam Q2 received by the light receiving system 20. In addition, the hologram image 4 based on the diffraction pattern 3 is formed on the hologram seal 2 as described above.

The projection system 10 includes a semiconductor laser 11 for emitting a laser measurement light beam Q1, and a collimator lens 12 for converting the laser measurement light beam Q1 emitted from the semiconductor laser 11 into a parallel light beam.

The light receiving system 20 includes a Fourier transform lens 21 located immediately above the hologram seal 2 and a line sensor 22 as a light receiving unit. The card 1 is inserted into a housing body (not shown) such that the hologram seal 2 is located at the front focal position (light receiving surface focal position) f of the Fourier transform lens 21. The line sensor 22 is located at the rear focal position f ′ of the Fourier transform lens 21 and, as shown in FIG. 1B, is arranged in parallel with the laser measurement light beam Q1 (indicated by the optical axis) in plan view. .
The front focal position f and the rear focal position f 'are equidistant.

The analysis / judgment unit 30 includes the line sensor 22
Pattern image Q2 'of diffracted reflected light beam Q2 formed on
(See FIG. 2 (A)) an analyzing unit 31 and an analyzing unit 3
A determination unit 32 that performs a true / false determination based on the signal output from 1 and a display unit 33 that displays the determination result.

In the above configuration, the semiconductor laser 11
Is turned on, the laser measurement light beam Q1 is incident on the hologram image 4 parallel to the line sensor 22 in a plan view while keeping the incident angle θ with respect to the hologram seal 2 constant.

In this example, the hologram image 4 is such that each diffraction pattern 3 has a predetermined pitch (for example, a constant pitch width of 1.0 μm) in a direction orthogonal to the extending direction of the line sensor 22.
It is assumed to be formed by The diffraction phenomenon is caused by an incident light vector component incident perpendicular to the direction in which the diffraction pattern 3 extends, of the laser measurement light beam Q1 of the parallel light beam incident on the diffraction pattern 3.

As a result, when the laser measurement light beam Q1 is incident on the hologram image 4, a diffraction pattern image (first-order diffraction light) Q2 'is formed on the line sensor 22 by the Fourier transform lens 21, as shown in FIG. It is formed so as to be located at.

The line sensor 22 is arranged such that the peak of the laser measurement light beam Q1 is located at the center address when the diffraction patterns 3 are ideally arranged at a constant pitch width.

On the other hand, the diffraction pattern 3 actually corresponds to FIG.
As shown in (C), there is a minimal variation. This variation exists in a very small range even if the hologram image 4 is created with high accuracy, but occurs in a large range when the hologram image 4 is rough. Hereinafter, for convenience of explanation, when the ideal pitch width of the diffraction pattern 3 is 1.0 μm, the pitch error of the diffraction pattern 3 of the hologram image 4 of the genuine card 1 is ± 0.
1 μm or less, and the depth H of the diffraction pattern 3.

When the hologram image 4 provided on the card 1 is authentic, a diffraction pattern image Q2 'of the diffraction pattern 3 is formed on the line sensor 22 substantially at the center address.

FIG. 2B shows the peak intensity P based on the depth H of the diffraction pattern 3, the peak position M based on the pitch width of the diffraction pattern 3, and the predetermined threshold w based on the variation in the pitch of the diffraction pattern 3. 5 shows a light amount distribution R expressed by a spread width W in FIG. The determination unit 32 stores the peak intensity P, the peak position M, and the spread width W as authenticity allowable reference values.

Here, as shown in FIG. 3C, a diffraction pattern image when the depth of the diffraction pattern 3 is a depth H2 smaller than the depth H of the diffraction pattern 3 of the genuine card 1 In Q3, the peak intensity P2 of the light amount distribution R1 is lower than the peak intensity P of the light amount distribution R.

As shown in FIG. 4C, the variation in the pitch of the diffraction pattern 3 is coarser (for example, ± 0.1 μm or less) than the variation in the diffraction pattern 3 of the genuine card 1 (for example, ± 0.1 μm or less). In the diffraction pattern image Q4 in the case of ± 0.2 μm or more, the spread width W2 of the light amount distribution R2 on the threshold w is wider than the spread width W of the light amount distribution R.

Further, as shown in FIG. 5C, the pitch width of the diffraction pattern 3 is larger than the pitch width of the diffraction pattern 3 of the genuine card 1 (for example, 1.0 μm). 0 μm), the peak position M2 of the light amount distribution R3 is shifted to the left from the peak position M of the light amount distribution R in the diffraction pattern image Q5.

In the above figures, the peak positions M of the light amount distributions R to R3 are used as references, but the light amount distributions R to R3
The center of gravity position indicated by may be used as a reference.

Accordingly, the analysis unit 31 is provided with the line sensor 2
These optical characteristics are analyzed and output to the determination unit 32. The determination unit 32 determines the authenticity of the output result and the previously stored peak intensity P, peak position M, and spread width W (standard deviation). A comparison is made with a judgment allowable reference value (statistical method), and when at least one of the values is different from the authenticity judgment allowable reference value or is larger than an allowable value in a predetermined range, it is determined that the card is a fake card. And displays the determination result on the display unit 3.
Output to 3.

For example, a line sensor 2 having a total number of n pixels
The pixel numbers of 2 are 1, 2,.
.., I,... N, and the photoelectric output of each pixel is Xi. First, a maximum intensity (peak intensity P) on the line sensor 22 and a pixel number i indicating the maximum intensity are detected. From the photoelectric output Xi, a pixel number (peak position M) corresponding to the average value is calculated from the following equation (1).

[0036]

[Formula 1]

The spread W of the light quantity distribution is obtained from the above equation (2).

At this time, of the photoelectric output Xi, those having a pixel number indicating a value equal to or less than a predetermined value are not used in the calculation by the above formula.

Accordingly, the analysis unit 31 performs a calculation based on the above-described equations (1) and (2), and has a function of temporarily storing the calculation result and a function of temporarily storing the peak intensity P. It has.

On the other hand, as shown in FIG.
The apparatus includes an allowable value control unit 34, comparators 34a, 34b, 34c, allowable value setting units 35a, 35b, 35c, and an overall judgment unit 36.

The allowable value setting unit 35a sets the allowable range of the peak intensity P of the light amount distribution, and the allowable value setting unit 35b sets the allowable range of the center of gravity M of the light amount distribution.
c sets the allowable range of the spread width W of the light amount distribution.

Even in the case of the genuine card 1, since the peak intensity P, the center of gravity M, and the spread width W of the light quantity distribution of the diffraction pattern 3 forming the hologram image 4 may be different, each allowable value setting unit 35a , 35b, 35c is desirably controlled by the tolerance control unit 34.

The comparator 34a receives an analysis output relating to the peak intensity P analyzed by the analyzer 31 and outputs the result to the comparator 34a.
The analysis output regarding the center-of-gravity position M analyzed by the analysis unit 31 is input to b, and the analysis output regarding the spread width W analyzed by the analysis unit 31 is input to the comparator 34c.

The comparator 34a compares whether or not there is an analysis output relating to the peak intensity P in the allowable range of the peak intensity for the card authenticity set by the allowable value setting unit 35a. The comparator 34c compares whether or not there is an analysis output related to the center of gravity position M within the allowable range of the center of gravity set by 35b, and the comparator 34c expands to the allowable range of the card width authenticity set by the allowable value setting unit 35c. It is compared whether or not there is an analysis output related to the width W.

The results of these comparisons are input to the overall judgment section 36, which determines whether the card is a genuine card or a fake card based on the results of these comparisons, and displays the judgment result on the display section 50. Is done.

As described above, according to the embodiment of the present invention, whether the authenticity card is a genuine card or a fake card is determined by determining whether the peak intensity P, the center of gravity M, and the spread width W of the light quantity distribution are within the allowable range. By determining whether the hologram image 4 is true or false based on the entire image of the hologram image 4 or a partial image in a wide range, it is possible to determine whether the analysis grid 3 in a narrower range is strict or not. True / false judgment.

In the case of the genuine card 1, the surface of the diffraction pattern 3 is worn out or finely scratched due to, for example, aging due to frequent use. If the allowable ranges of the peak intensity P, the center of gravity position M, and the spread width W of the light quantity distribution are strict, there is a possibility that the card may be determined to be a fake card despite being a genuine card. It is also possible to slightly increase the peak intensity P) caused by the depth of the diffraction pattern 3.

At this time, in consideration of the above-mentioned aging and the like,
Although any one of the peak intensity P, the center of gravity position M, and the spread width W of the light amount distribution is not included in the strictly close allowable range,
If the card is located at a position slightly deviated from the strict allowable range, it is determined as a genuine genuine card in a pseudo range different from the disguise range, and the fact is displayed on the display unit 33. For example, the card 1 is used. For example, it is possible to prompt a store clerk or the like to visually confirm deterioration or damage, or to prompt a user to replace a card due to severe damage.

[0049]

As described above, according to the card authenticity determining apparatus of the present invention, the authenticity determination as to whether the card is a genuine card or a fake card is performed by determining the whole image of the hologram image or the partial image in a wide range. Instead of making a true / false decision, it is possible to make a strict truth / false decision within a fine range of a narrower analysis grid that is difficult to disguise.

[Brief description of the drawings]

FIG. 1 shows a card authenticity judging device according to an embodiment of the present invention, (A) is a schematic side view of the card authenticity judging device,
(B) is a schematic plan view of the card authenticity determination device.

FIG. 2A is an explanatory diagram of a relative relationship between a diffraction pattern, a Fourier transform lens, and a line sensor, and FIG.
FIG. 4 is a graph showing a light amount distribution in the case of a genuine card, and FIG. 4C is an explanatory diagram for explaining the depth and variation of the diffraction pattern in the case of a genuine card.

3A is an explanatory diagram of a relative relationship between a diffraction pattern, a Fourier transform lens, and a line sensor, and FIG.
FIG. 7 is a graph showing a light amount distribution in the case of a camouflaged card having a shallow diffraction pattern, and FIG. 9C is an explanatory diagram for explaining a camouflage card having a shallow diffraction pattern.

FIG. 4A is an explanatory diagram of a relative relationship between a diffraction pattern, a Fourier transform lens, and a line sensor, and FIG.
FIG. 4 is a graph showing a light amount distribution in the case of a camouflaged card having a large variation in diffraction pattern, and FIG. 4C is an explanatory diagram for explaining a camouflage card having a large variation in the diffraction pattern.

FIG. 5A is an explanatory diagram of a relative relationship between a diffraction pattern, a Fourier transform lens, and a line sensor, and FIG.
FIG. 7 is a graph showing a light amount distribution in the case of a camouflaged card having a large pitch width of a diffraction pattern, and FIG. 7C is an explanatory diagram for explaining a camouflage card having a large pitch width of a diffraction pattern.

FIG. 6 is also a block diagram of a determination circuit.

FIG. 7A is a front view of a card having a hologram seal stuck on its surface, and FIG. 7B is an enlarged view of the hologram seal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Card 2 ... Hologram seal 3 ... Diffraction pattern 4 ... Hologram image 10 ... Projection system 20 ... Light receiving system 21 ... Fourier transform lens 22 ... Line sensor (light receiving part) 32 ... Judgment part Q1 ... Laser measurement light beam Q2 ... Diffraction reflected light beam

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C005 HA02 HB09 JA18 JB08 LA19 LB17 LB52 2K008 AA13 CC03 EE04 FF21 HH01 HH06 HH28 3E041 AA10 BA11 BB01 CA01 CA03 5B072 AA02 CC02 CC35 DD02 GG07 LL07 LL12 LL18

Claims (8)

[Claims] 1. A projection system provided on a card surface and projecting a laser measurement light beam toward a hologram image formed by a diffraction pattern, and a diffraction pattern image formed on a light receiving portion by a diffraction reflection light beam reflected from the hologram image. A card authenticity determining apparatus comprising: a light receiving system having a Fourier transform lens to be formed; and a determining unit for determining the authenticity of a hologram image based on a signal from the light receiving unit. 2. The card authenticity judging device according to claim 1, wherein said judging section includes a display section for displaying the judgment result. 3. The method according to claim 1, wherein the determination unit determines the authenticity of the hologram image based on an analysis result from an analysis unit for analyzing the diffraction pattern image. Card authenticity judgment device. 4. The authenticity of the card according to claim 3, wherein the analysis unit analyzes a formation position, a peak intensity, and a spread width of the diffraction pattern image and outputs the analysis result to the determination unit. Judgment device. 5. When the determination unit determines that all of the diffraction pattern image formation position, peak intensity, and spread width are genuine, the determination unit determines that the card is a genuine card and that the card is a genuine card. 5 is displayed on the display unit. 6. When the determination unit determines that at least one of the formation position, the peak intensity, and the spread width of the diffraction pattern image is a fake, the determination unit determines that the card is a fake card. The card authenticity judging device according to claim 4, wherein the card is displayed on the display unit. 7. The determination unit determines that the card is a genuine card when all of the formation position, peak intensity, and spread width of the diffraction pattern image are genuine. If only one is determined to be a pseudo card within the predetermined analysis range, it is determined to be a temporary genuine card, and if it is determined that at least one of the cards is a counterfeit card, it is determined to be a pseudo card. 5. The card authenticity determination device according to claim 4, wherein the determination result is displayed on the display unit. 8. The apparatus according to claim 4, wherein when there are a plurality of types of pitches or directions of the diffraction pattern, the determination unit makes a determination based on an analysis result for one or all of the types. Card authenticity judgment device.