JPH0795340B2 - Identification method and identification structure of information storage card - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is set in a reader / writer so as to prevent forgery of an information storage card such as a magnetic card, an IC card, an optical card, etc., for exchanging information with the reader / writer. The present invention relates to a method and an identification structure for identifying a card as a legitimate card.

[0002]

2. Description of the Related Art Conventionally, for example, a bar code or a magnetic bar code is provided on the surface of a card to prevent the magnetic card from being forged, or a magnetic card which is not reused is used after being used on the magnetic recording surface. Although methods such as punching holes have been carried out, in each of the above methods, the forgery side can relatively easily analyze the structure and can forge the card using a relatively inexpensive device. There was a problem to say.

Therefore, Japanese Patent Application No. Hei.
No. 209065, a means for irradiating a reader / writer with illumination light toward the reflection surface portion of the card, and a diffracted reflection light from the reflection surface portion are provided with a hologram reflection surface portion having a unique reflection direction characteristic on the card surface. Light receiving means for receiving light at a position corresponding to its reflection direction characteristic, and means for identifying whether the card set in the reader / writer is an authorized card or not based on the intensity of light received by this light receiving means. The identification structure of the constructed card is described. A structure using a diffraction grating as the reflecting surface portion is disclosed in Japanese Patent Application No. 1-209066, and a structure using a large number of parallel V-shaped or U-shaped grooves as the reflecting surface portion is disclosed in Japanese Patent Application No. 1-21066.
No. 09067.

In the identification structure in each of the above-mentioned specifications, when the card is set in the reader / writer, illumination light is emitted toward the reflection surface portion of the card, the reflected light is received by the light receiving surface portion, and the received light is received. If the strength is equal to or higher than a predetermined value, the card is identified as an authorized card.

According to this identification structure, not only is it difficult to analyze the reflecting surface portion for the purpose of counterfeiting a card, but it also requires a great deal of cost to make the reflecting surface portion made of a diffraction grating, a hologram or the like. Therefore, it is virtually impossible to forge a card similar to a legitimate card.
Further, the card is identified by a simple structure in which the reflecting surface is irradiated with illumination light, the intensity of the light received by the light receiving means is photoelectrically converted, and compared with a predetermined threshold voltage. The equipment provided does not become large or complicated.

[0006]

However, in the above identification structure, even if the card set in the reader / writer is a legitimate card, if the reflection efficiency of the reflecting surface portion is low due to dirt or the like, the light receiving means receives light. The intensity of the emitted light does not become higher than the predetermined value, and in some cases, it is possible that this card is mistakenly recognized as an unauthorized card. Also,
On the other hand, even if the card set in the reader / writer is not a legitimate card, if the entire surface of the card is a highly reflective color such as white, it will diffuse the illumination light, so this card may be legitimate in some cases. It is possible to misidentify it as a card. Therefore, the actual identification process, that is, the scan
Before scanning, memorize the result by pre-scan,
To evaluate the reading error due to the influence of background.
Raw data after compensation and actual scanning
Once, and evaluate the entire scanning result once
Compensation of reading errors due to background effects
It may be possible to identify them by using a large amount of memory and multiple
The problem that a coarse evaluation circuit is required and the output is slow
There was a problem.

Therefore, the present inventors have pointed out that the reflection efficiency of the reflection surface portion of the card is reduced, and the reflection efficiency of the card other than the reflection surface portion is also deteriorated due to dirt, and the illumination light is diffusely reflected on the entire surface of the card. Paying attention to the fact that the card also increases the intensity of reflected light in directions other than the direction corresponding to the reflection direction characteristic of the reflective surface section in a regular card, the light reflected at the position corresponding to the reflection direction characteristic of the reflective surface section Simultaneous not only strength
Considering also the intensity of the light reflected at a position not corresponding to the reflection direction characteristic of the reflective surface portion, reliably whether <br/> card inserted into the reader-writer is a legitimate card, and early
I came to think of something that can be identified.

In view of the above problems of the prior art, the main object of the present invention is that the card forgery prevention effect is high and that the card set in the reader / writer is an authorized card.
Does not require huge memory and complicated evaluation circuit
In addition, it is an object of the present invention to provide an identification method and an identification structure of an information storage card that can be reliably identified without slowing down processing .

[0009]

According to the present invention, such an object is achieved in a reader / writer for exchanging information with an information storage card having a reflective surface portion having a unique reflective direction characteristic on its surface. A method of identifying an information storage card for identifying that the card is a regular card, which comprises irradiating illumination light toward the reflecting surface portion and not corresponding to a position corresponding to a reflection direction characteristic of the reflecting surface portion. The intensity of the light received at the plurality of light receiving surface portions provided at the position and received at the position corresponding to the reflection direction characteristic of the reflecting surface portion is the average value of the intensity of the light received at each light receiving surface portion at the same time. Is higher than a threshold value obtained by adding a predetermined value to the information storage card identification method, characterized in that the card is identified as a legitimate card, or has a reflective surface portion having a unique reflection direction characteristic on the surface. An information storage card identification structure for identifying that the card is a legitimate card by a reader / writer that sends and receives information to and from the information storage card, and illuminates the reflecting surface section with illumination light. Means to do
Means for receiving light at a plurality of light receiving surface portions provided at positions corresponding to and not corresponding to the reflection direction characteristics of the reflection surface portion, and a predetermined value added to the average value of the intensity of light received at each light receiving surface portion. Means for setting a threshold value and means for identifying the card as an authorized card if the intensity of light received at a position corresponding to the reflection direction characteristic of the reflection surface portion is higher than the threshold value set at the same time. It is achieved by providing an identification structure for an information storage card, characterized in that

[0010]

According to the above construction, it is possible to determine whether or not the card set in the reader / writer is a proper card only by measuring the light receiving intensity of each light receiving surface regardless of the surface color of the card or the state of dirt. Can be identified.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment to which the present invention is applied.
It is a perspective view which shows typically the principal part structure in the magnetic card 1 and a card reader / writer.

The card 1 is driven in the direction indicated by the arrow in the card reader / writer, that is, in the substantially left-right direction in FIG. 1, by a not-shown conveying roller or the like, and is provided on the main surface 1a of the card 1 by the magnetic head 3. Information is written to and / or read from the magnetic stripe 2.

A hologram portion 4 as a light receiving surface portion is provided on the main surface 1a of the card 1 at a position parallel to the magnetic stripe 2. The hologram section 4 includes four hologram reflection surfaces 4a, 4a arranged along the carrying direction of the card 1.
It consists of b, 4c and 4d. These hologram reflecting surfaces 4
Reference numerals a, 4b, 4c, and 4d denote diffraction direction characteristics as reflection direction characteristics for reflecting, diffracting, and converging illumination light having a predetermined wavelength, which is emitted from a direction directly facing the hologram, in respective peculiar directions. It has a reflection hologram.

On the other hand, when the card 1 is at the position shown by the solid line in FIG. 1 on the card reader / writer side, the hologram reflecting surface 4a is located at a position directly facing the hologram reflecting surface 4a on the main surface 1a. On the other hand, a light emitting element 5 as a means for irradiating laser light is provided at a predetermined interval. The light emitting element 5 faces the hologram reflecting surfaces 4a, 4b, 4c, and 4d in order as the card 1 is conveyed. The light emitted from the light emitting element 5 is reflected by the hologram reflection surfaces 4a, 4b, 4c, and 4d according to its diffraction direction characteristics, diffracted, and condensed at each position to receive light as four light receiving surface portions including photodiodes. Element 7
10 are provided.

Therefore, the reflecting surface 4a and the light receiving element 7, the reflecting surface 4b and the light receiving element 8, the reflecting surface 4c and the light receiving element 9, and the reflecting surface 4
d and the light-receiving element 10 correspond to each other. For example, in FIG. 1, the illumination light from the light-emitting element 5 is reflected by the hologram reflection surface 4a.
Is reflected and diffracted toward the light receiving element 7 to be condensed, but as shown in FIG. 2, the illumination light from the light emitting element 5 is reflected and diffracted toward the light receiving element 8 by the hologram reflection surface 4b and condensed. Let

Each of the light receiving elements 7 to 10 is connected to an identification unit 11 for identifying whether or not the card 1 is an authorized card. As shown in FIG. 3, the identification unit 11 includes amplifiers 13 to 16 connected to the output sides of the respective light receiving elements 7 to 10.
And an average voltage calculating circuit 17 for averaging the output voltages from the amplifiers 13 to 16 and outputting the average voltage, and an offset voltage adding circuit 18 for adding a predetermined offset voltage to the output voltage from the average calculating circuit 17. Threshold setting means, comparators 19 to 22 for comparing the output voltage from each amplifier 13 to 16 with the output voltage from the offset voltage adding circuit 18, that is, the threshold voltage, and each comparator 1.
9 to 22 and an identification circuit 23 provided on the output side. In this identification circuit 23, each comparator 19-22
With the output value of, it is possible to identify whether or not the card 1 is actually a regular card.

In order to actually identify the card 1, the illumination light is emitted from the light emitting element 5 while the card 1 inserted in the card reader / writer is being conveyed. Then, the reflected light is received by each of the light receiving elements 7 to 10. These light receiving elements 7 to
The output voltage of 10 is amplified by the amplifiers 13 to 16 to be output voltages V1 to V4, the threshold voltage Vs is obtained by the average calculation circuit 17 and the offset voltage adding circuit 18, and the threshold voltage Vs and the outputs from the amplifiers 13 to 16 are obtained. The voltages V1 to V4 are compared with each other by the comparators 19 to 22, and if the voltage on the amplifier side is higher, it is determined that the signal is based on the diffraction direction characteristic of the reflection surface portion corresponding to the light receiving element, and the voltage V1H is supplied to the identification circuit 23. Outputs ~ V4H. Then, the identification circuit 23
Then, the voltages of all the comparators 19 to 22 are added to calculate the identification signal VJ shown by the solid line in FIG. 4 to identify that the card 1 is a normal card. That is, the reflecting surface 4a is recognized at the position where the hologram reflecting surface 4a and the light emitting element 5 face each other (the position shown by the solid line in FIG. 1), and each reflecting surface 4a is similarly recognized.
b, 4c, and 4d are recognized from the output voltages from the comparators 19 to 22 to identify that the card 1 is a normal card.

Here, the threshold voltage Vs is set to the value of each of the light receiving elements 7 ...
Output voltage V from 10 (actually each amplifier 13 to 16)
1 to V4 are averaged (Va), and the offset voltage Vo
Since it is set by adding
As shown by the imaginary line in Fig. 2, when the reflection efficiency of each of the reflecting surfaces 4a, 4b, 4c, 4d is low due to dirt or the like, the average voltage is low, that is, the threshold voltage Vs (L).
Therefore, if any of the output voltages V1 to V4 is relatively higher than the other output voltages, the reflective surfaces 4 can be easily processed.
The signals based on the diffraction direction characteristics of a, 4b, 4c, and 4d can be recognized. Further, as shown by an imaginary line in FIG. 5, contrary to the above, for example, when the entire main surface 1a of the card 1 has a color with a high reflectance such as white, or when the illumination light is diffusely reflected, Since the average voltage increases and the threshold voltage Vs (M) also increases, one of the output voltages V1 to V4 is relatively higher than the other output voltage and the threshold voltage Vs
If it is higher than (M), each reflecting surface 4a,
A signal based on the diffraction direction characteristics of 4b, 4c, and 4d can be recognized.

In the present embodiment, the light receiving elements 7 to 10 are individual light receiving elements, but in reality, one multi-divided photodiode can be used. Further, the number of reflecting surfaces and light receiving portions is not limited to four, and an arbitrary number of light receiving surfaces having different diffraction direction characteristics are provided on the card surface, and a corresponding number of light receiving portions are provided on the card reader / writer side. good. Furthermore, in the present embodiment, the reflecting surface having the characteristic of the characteristic of the diffracting direction is constituted by the reflection hologram, but it is not limited to this, and it is constituted by the diffraction grating and a large number of U-shaped or V-shaped grooves having the characteristic of the characteristic of the reflecting direction. You may.

It is needless to say that the present invention is not limited to the above-described embodiments and can be applied in various ways. For example, in each of the above-described embodiments, illumination light is directly emitted from the light emitting element to the hologram portion through a lens. Although irradiation is performed, a mirror, a prism or the like may be inserted in the optical path to change the optical path. Further, although the photodiode is used as the light receiving element in each of the above embodiments, the positioning sensing device (PS
D) may be used.

[0022]

As is apparent from the above description, according to the present invention, the illumination light is irradiated toward the reflecting surface portion having the unique reflection direction characteristic provided on the surface of the information storage card, and the reflection of this reflecting surface portion. The intensity of the light received by the multiple light-receiving surface portions provided at the positions corresponding to the directional characteristics and at the positions not corresponding to the directional characteristics, and the intensity of the light received at the positions corresponding to the reflection direction characteristics of the reflecting surface portion are also received at each light-receiving surface portion If it is higher than the threshold value obtained by adding a predetermined value to the average value of the light intensity, the card is identified as a legitimate card so that each light received is irrespective of the surface color of the card or the state of dirt. Only by measuring and comparing the received light intensity of the surface part, it is possible to quickly determine whether the card set in the reader / writer is a regular card ,
In addition, since the card can be surely identified, the identification reliability of the card is improved and its structure is not complicated. From the above, the effect of the present invention is great.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a magnetic card and a card reader / writer showing a preferred embodiment according to the present invention.

FIG. 2 is a view similar to FIG. 1 showing an operating procedure in an embodiment according to the present invention.

FIG. 3 is a schematic circuit diagram showing a circuit configuration of the identification unit of FIG.

FIG. 4 is a time chart showing an operating procedure in the embodiment according to the present invention.

FIG. 5 is a time chart similar to FIG. 4, showing an operating procedure in an embodiment according to the present invention.

FIG. 6 is a time chart similar to FIGS. 4 and 5, showing an operating procedure in the embodiment according to the present invention.

[Explanation of symbols]

 1 Card 1a Main surface 2 Magnetic stripe 3 Magnetic head 4 Hologram part 4a, 4b, 4c, 4d Hologram reflection surface 5 Light emitting element 7-10 Light receiving element 11 Identification unit 13-16 Amplifier 17 Average calculation circuit 18 Offset voltage addition circuit 19- 22 Comparator 23 Identification circuit

Claims (4)

[Claims] 1. A reader / writer for exchanging information with an information storage card having a reflection surface portion having a unique reflection direction characteristic on its surface, for identifying that the card is an authorized card. A method of identifying a memory card, which comprises illuminating the reflecting surface portion with illumination light, receiving light at a plurality of light receiving surface portions provided at positions corresponding to and not corresponding to a reflection direction characteristic of the reflecting surface portion, If the intensity of the light received at the position corresponding to the reflection direction characteristic of the reflection surface portion is higher than the threshold value obtained by adding a predetermined value to the average value of the intensity of the light received at each light receiving surface portion at the same time, the card is A method for identifying an information storage card, which is characterized in that the card is identified as a legitimate card. 2. The information storage card includes a plurality of reflecting surface portions each having a reflecting direction characteristic different from each other, and the plurality of light receiving surface portions corresponding to the reflecting direction characteristics of each reflecting surface portion. Light which is made up of a surface portion and which is sequentially irradiated with illumination light toward each of the reflection surface portions, is received by each of the light receiving surface portions, and is received at a position corresponding to the reflection direction characteristic of each of the reflection surface portions that is illuminated with the illumination light. Is higher than the threshold value obtained by adding a predetermined value to the average value of the intensities of the light received on the respective light-receiving surface portions at the same time at the time of irradiation of the illumination light on the respective reflection surface portions, The information storage card identification method according to claim 1, wherein the information storage card is identified as a card. 3. An information storage for identifying that the card is a regular card by a reader / writer for exchanging information with an information storage card having a reflection surface portion having a unique reflection direction characteristic on its surface. In the card identification structure, means for irradiating the reflecting surface portion with illumination light, and means for receiving light at a plurality of light receiving surface portions provided at positions corresponding to and not corresponding to the reflection direction characteristic of the reflecting surface portion A means for setting a threshold value by adding a predetermined value to the average value of the intensity of the light received by each of the light receiving surfaces, and the intensity of the light received at the position corresponding to the reflection direction characteristic of the reflective surface. An identification structure for an information storage card, comprising means for identifying the card as a legitimate card if it is higher than the threshold value set at the same time. 4. The reflection surface section of the information storage card is composed of a plurality of reflection surface sections having different reflection direction characteristics, and the plurality of light receiving surface sections are provided at positions corresponding to the reflection direction characteristics of the respective reflection surface sections. A plurality of light-receiving surface portions, the illumination light irradiating means comprises means for sequentially irradiating the reflecting surface portions with the illuminating light, and the identifying means has a reflection direction characteristic of each reflecting surface portion irradiated with the illuminating light. 7. If the intensity of the light received by the light-receiving surface portion corresponding to is higher than the threshold value set by the threshold value setting device at the same time, the card is identified as a regular card. 3. An identification structure of the information storage card described in 3.