JPH1153703A - Detected article to be checked on genuineness, method for checking genuineness of the same and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the detected article to be effective in preventing forgery and illegal use by obtaining more various detecting signals than heretofore. SOLUTION: The detected article 10 is equipped with a large number of 1st magnetic elements 12 consisting of a magnetic material of magnetically soft quality and low coercive force and a large number 2nd magnetic elements 13 consisting of a magnetic cterial of magnetically hard quality and high coersive force, which are mixed at random in a scanning area 17. The device for processing the article 10 is composed of a magnetizer for giving a magnetic field magnetizing the 2nd magnetic elements 13 to the scanning area 17, a magnetic sensor for obtaining a detecting signal scanning the scanning area 17 magnetically and a controller for enciphering data relative to the detecting signals obtained by scanning the scanning area 17 plural times in changing conditions of magnetizing the 2nd magnetic elements 13, etc. The detectionate is fudged to be genuine by the controller when the enciphered data recorded in a code display part and the detecting signals are correspondent to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cards such as important documents, banknotes and checks, traveler's checks, ID cards, CD cards, credit cards, etc., passports, works of art, public sports voting tickets, etc. The present invention relates to an object that needs to be prevented from forgery, and a method and apparatus for checking the authenticity of the object.

[0002]

2. Description of the Related Art In order to check the authenticity of an object such as a document or a card, there is known a device in which a number of magnetic elements are randomly provided in a scanning area of the object. This type of device for checking the authenticity of an object is a magnetic sensor in a scanning area that is magnetically scanned by a magnetic sensor to generate a detection signal having a unique waveform corresponding to the distribution state of the magnetic elements. I'm trying to get.

When issuing an object to be detected, the detection signal is encrypted and the encrypted data is recorded in a code recording section of the object to be detected. When checking the authenticity of the object, a detection signal is obtained by magnetically scanning the scanning area by the magnetic sensor, and the detection signal is compared with the encrypted data recorded in the recording unit. Then, when both correspond, the detected object is determined to be authentic.

[0004]

In the above-mentioned conventional apparatus, the scanning area is scanned no matter how many times by the magnetic sensor.
Basically, the same detection signal is reproduced.
That is, one specific type of waveform is detected according to the distribution of the magnetic elements in the scanning region.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an object to be detected, which is more effective in preventing forgery and unauthorized use, and to provide a method and an apparatus for checking the object, in which a variety of detection signals can be obtained as compared with the prior art. is there.

[0006]

The object to be detected according to the present invention, which has been developed to achieve the above object, is randomly mixed in a scanning area of a substrate and is magnetically mixed. A large number of first magnetic elements made of a soft, low coercive magnetic material and a large number of second magnetic elements made of a magnetically hard, high coercive magnetic material mixed randomly in the scanning area and magnetically hard.
And a code display unit for recording data relating to a detection signal obtained by magnetically scanning the scanning area a plurality of times by changing the magnetization state of the second magnetic element. It is a feature.

As the first magnetic element, a fibrous thin wire made of a magnetically soft high-permeability magnetic material such as permalloy, sendust, Co-based amorphous, soft ferrite, or a powder made of such a material is used. A fiber or flake-like magnetic polymer element obtained by mixing a body in a synthetic resin is suitable. The coercive force of the first magnetic element is preferably in the range of 10 to 200 Oe, and the magnetic permeability is preferably in the range of 100 to 10,000.

[0008] As the second magnetic element, for example, ferrite, Sm-Co alloy, Nd alloy, Fe-Al-Co alloy,
A fibrous thin wire made of a magnetically hard material having a high coercive force, such as an Fe-Cr-Co alloy, or a fiber or flake-shaped magnetic polymer element in which a powder made of such a material is mixed in a synthetic resin Is suitable. The coercive force of the second magnetic element is desirably in the range of 500 to 3500 Oe. Each of the first magnetic element and the second magnetic element has a diameter or a width of, for example, about 5 to 100 μm, and a length of, for example, about 1 to 30 mm.

The checking method of the present invention includes a creation process for creating the object to be detected and a collation process for checking the object to be detected. The producing process includes a detecting step of obtaining a detection signal by magnetically scanning the scanning region a plurality of times by changing the magnetization state of the second magnetic element, and a writing step of recording data relating to the detection signal on a code display unit. Steps. The collation process includes a detection step similar to the creation process, a code reading step of reading data recorded on the code display unit, and determining that the detected object is authentic when the data corresponds to the detection signal. Determining step. The code display section may be provided on the detected object itself, or may be set in a storage area of a host computer or the like.

The apparatus according to the present invention comprises: a magnetizer capable of applying a magnetic field sufficient to magnetize the second magnetic element to a scanning area and switching magnetization conditions such as the direction and magnitude of the magnetic field;
A magnetic sensor that obtains a detection signal by magnetically scanning the scanning region; a unit that encrypts data related to a detection signal obtained by scanning the scanning region a plurality of times while switching the magnetization condition; Code writing means for recording the encrypted data on the code display of the detected object, reading means for reading the data recorded on the code display, collating the data with the detection signal, and Means for determining that the detected object is authentic when they correspond to each other.

[0011] As the above magnetic sensor, a magnetoresistive element (MR element) whose resistance value changes in proportion to the strength of a magnetic field.
A combination of a magnetoelectric conversion element such as the above and a magnet for generating a bias magnetic field is suitable. However, other than the MR element, for example, an element such as a magnetic diode or a Hall element whose electrical characteristics such as a resistance value changes according to the strength of a magnetic field may be used.

When the coercive force of the first magnetic element is H1, the coercive force of the second magnetic element is H2, the magnitude of the magnetic field of the magnetizer is B1, and the magnitude of the bias magnetic field of the magnetic sensor is B2. , H1 <B2 <H2 <B1.

When the authenticity of the object to be detected is checked in the apparatus of the present invention, the magnetization state of the second magnetic element is switched by changing the direction and magnitude of the magnetization magnetic field exerted on the scanning area by the magnetizer. While scanning the scanning area at least twice. By doing so, different detection signals can be obtained between the first scan and the second scan even though the distribution of the magnetic elements is the same. By using a plurality of types of detection signals to check the authenticity of the detection object, the accuracy of the check is increased, and the detection object that is more difficult to forge is obtained.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, a large number of first magnetic elements 12 and a large number of second magnetic elements 13 are oriented in unspecified directions in a base material 11 of a detection object 10 in the form of a card. Are randomly mixed in. The substrate 11 is made of a non-magnetic material such as paper or plastic.

The first magnetic element 12 is made of a magnetically soft material having a low coercive force and a high magnetic permeability, such as permalloy, sendust, soft ferrite, Co-based amorphous, and Fe-Ni-based alloy. The second magnetic element 13 is made of, for example, ferrite, Sm-Co alloy, Nd alloy, Fe-Al-C
It is made of a magnetically hard high coercive force material such as an o-alloy or an Fe-Cr-Co alloy.

The sectional shape of the magnetic elements 12 and 13 is not limited to a circle, but may be, for example, a polygon, a rectangle, an oval, or other forms. The magnetic elements 12 and 13 in the illustrated example are fibrous, but may be foil or powder. Also,
The fibrous material, the foil and the powder may be mixed. Also,
A fibrous or band-shaped magnetic polymer element in which a magnetic powder made of the above magnetic material is mixed in a polymer material such as an acrylic resin may be used. These magnetic elements 12, 13
Is a specific scanning area 17 when the object 10 is manufactured.
Is randomly mixed so as to be contained at a certain density.

A code display section 18 is provided on the object 10. When the scanning area 17 is magnetically scanned a plurality of times as described later,
Data concerning the unique detection signal obtained according to the distribution state of the data 13 is encrypted and written by the processing device 20 illustrated in FIG.

The processing apparatus 20 includes a housing 21 and a transfer mechanism 22. The transfer mechanism 22 has a transfer member 24 such as a belt or a roller driven by a forward / reverse rotatable motor 23 such as a DC motor. The motor 23 is rotated forward or backward by the motor control circuit 25 so that the object 10 can be reciprocated in the directions indicated by arrows F and R at a predetermined speed.

The magnetizer 3 is located halfway along the movement path of the object 10.
0 and a magnetic sensor 31 are provided. An example of the magnetizer 30 is a magnetizing power supply circuit 32 capable of switching the polarity.
Is connected to the electromagnet 33. The magnetizing power supply circuit 32 supplies a DC current to the electromagnet 33, and can change the magnitude of the current. Therefore, the electromagnet 33 can change the magnetization conditions such as the direction and magnitude of the magnetic field exerted on the scanning area 17.

The magnetic sensor 31 includes a first MR element 35 and a second MR element 36 as an example of a pair of magnetoelectric transducers.
It has. These MR elements 35 and 36 are arranged in the moving direction (scanning direction) of the detection object 10. Behind the MR elements 35 and 36, a magnet 37 for generating a bias magnetic field is arranged. The magnet 37 may be a permanent magnet, or an electromagnet using an electromagnetic coil may be used.

The MR elements 35 and 36 are magnetoresistive elements whose electric resistance changes according to the strength of the magnetic field. These M
The R elements 35 and 36 are electrically connected to each other, and a magnetic field of the same strength by the magnet 37 is applied to each MR element 35 and 36. The first MR element 35 is connected to a DC power supply circuit 40. Second MR
The element 36 is connected to a controller 50 that functions as a control / calculation means.

The magnetic element 1 is located near the MR elements 35 and 36.
When the magnetic elements 12 and 13 pass, the output voltage changes as the positions of the magnetic elements 12 and 13 change. That is, when the magnetic elements 12 and 13 do not exist near the MR elements 35 and 36, the magnetic field of the magnet 37 is uniformly applied to the MR elements 35 and 36. In this case, since the resistance values of the MR elements 35 and 36 are equal to each other, the output voltage is about half the input voltage. The magnetic elements 1 are located near the MR elements 35 and 36.
When the magnetic fluxes 2 and 13 pass, the magnetic flux passing through the respective MR elements 35 and 36 changes with time according to the positions of the magnetic elements 12 and 13, and the resistance values of the respective MR elements 35 and 36 are different. The output voltage changes.

The magnitude of the output voltage changes according to the distribution density of the magnetic elements 12 and 13 and the distribution state such as the diameter (or thickness), length, and direction of the magnetic elements 12 and 13. The output voltage of the waveform is detected.

Here, the coercive force of the first magnetic element 12 is H
1, the coercive force of the second magnetic element 13 is H2, the magnitude of the magnetic field (magnetizing magnetic field) of the magnetizer 30 is B1, and the magnitude of the bias magnetic field exerted on the scanning area 17 by the magnet 37 of the magnetic sensor 31 is B2. Then, H1 <B2 <H2 <B1. In other words, when the scanning area 17 passes near the magnetizer 30 and then passes near the magnetic sensor 31, the second high coercive force
Of the magnetic element 13 is magnetized (magnetized) by the magnetizing magnetic field B1.
Since the magnetized state is maintained, it is hardly affected by the bias magnetic field B2 of the magnetic sensor 31. Therefore, the magnetically hard second magnetic element 13 has the magnetizing magnetic field B
1 is detected by the magnetic sensor 31.

The processing device 20 includes a controller 50 using a microcomputer or the like, a code writing unit 51 for recording the following encrypted data in the code display unit 18 of the object 10, and a code recording unit 51 recorded in the code display unit 18. And a code reading unit 52 for reading the encrypted data. The code writing unit 51 and the reading unit 52 are connected to a read / write circuit 53. Controller 50
Includes an A / D converter 60, a comparator 61, an encryption code converter 62, and the like. The display 65 is connected to the controller 50.

Next, the operation of the processing device 20 will be described. FIG. 6 shows an outline of a process for creating the detection object 10. In the manufacturing step S1, a large number of first magnetic elements 12 and a large number of second magnetic elements 13 are randomly mixed into at least the scanning region 17 when the substrate 11 of the detection object 10 is manufactured. .

The detection step S2 includes a first scanning step S3 and a second scanning step S4. In the first scanning step S3, the electromagnet 33 generates a magnetic field of a predetermined magnetic pole while the object 10 is moved in the direction of the arrow F at a predetermined speed by the transfer mechanism 22, so that the second magnetic field having a high coercive force is generated. The element 13 is magnetized. Since the first magnetic element 12 is made of a magnetically soft material having a low coercive force,
Even if it is magnetized, its magnetic force is weak.

When the scanning area 17 moves to the position of the magnetic sensor 31, the two types of elements 12, 13 are moved.
A bias magnetic field is applied to the magnetic element 12 and the magnetic element 12 by the MR elements 35 and 36.
The output of the analog waveform according to the distribution state of No. 13 is obtained. In the first scan, the first magnetic element 12 having a low coercive force is magnetized again by the bias magnetic field of the magnetic sensor 31 because the coercive force is small even if the first magnetic element 12 having a low coercive force is magnetized by the magnetizer 30 in advance. Therefore, the output component of the first magnetic element 12 has, for example, a waveform W1 shown in FIG.
Becomes

On the other hand, the strongly magnetized second magnetic element 13 retains the magnetizing magnetic field irrespective of the bias magnetic field, so that its output component has, for example, a waveform W2 shown in FIG. 4B. . A waveform obtained by combining these two types of waveforms W1 and W2 is, for example, a waveform W4 shown in FIG.

After the first scanning is completed, in the second scanning step S4, the scanning area 17 is returned to the magnetizer 30 again by the reverse rotation of the motor 23. At this time, the magnetic pole of the electromagnet 33 is switched by switching the polarity of the power supply circuit 32 for magnetization. When the motor 23 rotates forward again in this state, the scanning area 1
While the 7 moves in the direction of arrow F at a predetermined speed, the second magnetic element 13 is magnetized by the magnetizer 30 in the direction opposite to the first scanning step S3.

When the scanning area 17 moves to the position of the magnetic sensor 31, the two types of elements 12, 13 are moved.
A bias magnetic field is applied to the magnetic element 12 and the magnetic element 12 by the MR elements 35 and 36.
The output of the analog waveform according to the distribution state of No. 13 is obtained. That is, the first magnetic element 12 having a low coercive force is magnetized again by the bias magnetic field of the magnetic sensor 31 because the first magnetic element 12 has a small coercive force even if it is magnetized in the opposite direction in advance by the magnetizer 30. Therefore, the output component of the first magnetic element 12 is the same as that of the first time, and remains the waveform W1 illustrated in FIG. 4A.

On the other hand, the second magnetic element 13 is strongly magnetized in the opposite direction, and maintains the opposite magnetization field regardless of the bias magnetic field.
The waveform W3 shown in FIG. These two types of waveforms W1
, W3 is a waveform W5 shown in FIG. 5B, for example.

By reversing the direction of the magnetizing magnetic field between the first scan and the second scan, two types of output waveforms W4 and W5 are detected. In the first scan, the scan of the scan area 17 is performed without magnetizing the magnetic element 13 (in a state where the magnetic element 13 is demagnetized), and in the second scan, the scan of the scan area 17 is performed by magnetizing the magnetic element 13. Scanning may be performed. In this case, a permanent magnet having a simple configuration can be used as the magnetizer 30. In other words, the magnetization condition referred to in this specification includes the presence or absence of magnetization of the second magnetic element 13 in addition to the direction and magnitude of the magnetization magnetic field. Further, three or more types of output waveforms may be obtained by performing the third or fourth scanning step while changing the strength of the magnetic field by the magnetizer 30.

The output voltages of the waveforms W4 and W5 are divided at every minute time, ranked in a plurality of stages, and digitized. Thus, a coded detection signal unique to the scanning area 17 is obtained.

In the encryption step S5, the detection signal is encrypted by the encryption code converter 62 in accordance with a specific rule. The data encrypted in this way
In the writing step S6, the data is recorded on the code display unit 18 by the magnetic head of the code writing unit 51. The code display section 18 of this embodiment is a magnetic band.
8 may be recorded as a bar code.

Whether the object 10 is authentic or not is also checked using the processing device 20. FIG. 7 shows an outline of a collation process for checking the authenticity of the detection object 10. The detection step S11 includes a first scanning step S3 and a second scanning step S4, which are the same as the above-described creation process, and switches the magnetizing conditions by the magnetizer 30 in the same manner as in the creation process. By scanning the scanning region 17 twice or more, a detection signal corresponding to the distribution of the magnetic elements 12 and 13 is obtained.

In the code reading step S12,
Data (encrypted data) recorded on the code display section 18 is read by the code reading section 52. In the code reproduction step S13, the encrypted data is decrypted by the encryption code converter 62 based on a predetermined rule, whereby the verification code is reproduced. Then, in the discrimination step S14, the comparison code and the detection signal detected in the detection step S11 are compared by the comparator 61. When the two correspond, the detected object 1
0 is determined to be genuine, and the collation result is displayed on the display 65.
Will be displayed.

In order to enhance the security of the object 10, the scanning area 17 may be demagnetized by a degausser (not shown) when the object 10 is ejected from the processing device 20. . In that case, the electromagnet 3 of the magnetizer 30
By connecting an AC power supply to 3, a degausser may be used, or a separate degausser may be provided.

[0039]

According to the first aspect of the invention, various detection signals can be obtained in accordance with the distribution state of the first and second magnetic elements mixed in the scanning area and the combination thereof, and the forgery can be obtained. An object to be detected which is effective in preventing prevention and unauthorized use can be obtained. That is, in the present invention, not only the distribution state of each magnetic element, but also the mixed state of the first magnetic element and the second magnetic element is used to check the authenticity as representing the characteristics of the detected object.

According to the check method of the present invention, various detection signals can be obtained by the distribution states of the first and second magnetic elements and their combinations, which is effective in preventing forgery and unauthorized use. It is. Further, if the scanning region is scanned three or more times and the magnitude of the magnetizing magnetic field and the direction of the magnetic field are changed in each scanning, further various characterizations can be performed.

According to the processing apparatus of the third aspect, the authenticity of the detection object in which the first magnetic element having the low coercive force and the second magnetic element having the high coercive force are randomly mixed in the scanning area is determined. In checking, it is possible to check whether the detected object is genuine according to the distribution state and the mixed state of the first magnetic element and the second magnetic element.

According to the processing device of the fourth aspect, M
When using a magnetic sensor in which a magnetoelectric conversion element such as an R element and a magnet for generating a bias magnetic field are used, the first magnetic element having a low coercive force exceeds the coercive force by the magnetic sensor even when magnetized by the magnetizing magnetic field. Since the magnetic field is applied, the magnetization due to the bias magnetic field is detected. The second magnetic element having a high coercive force is magnetized (magnetized) by the magnetizing magnetic field, and is held by the magnetic element, and is hardly affected by the bias magnetic field of the magnetic sensor. Therefore, the magnetization by the magnetizing magnetic field is detected by the magnetic sensor. You. In this way, various detection signals can be obtained by a plurality of scans.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing an object to be detected according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a part of the detected object shown in FIG.

FIG. 3 is a side view schematically showing a partial cross section of the apparatus for processing an object shown in FIG. 1;

FIG. 4 is a waveform chart showing output components of a first magnetic element and a second magnetic element.

FIG. 5 is a waveform chart showing a combined output of a first magnetic element and a second magnetic element.

FIG. 6 is a flowchart showing steps of a process when creating an object to be detected.

FIG. 7 is a flowchart showing the steps of a process when matching an object to be detected.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Detection object 11 ... Base material 12 ... 1st magnetic element 13 ... 2nd magnetic element 17 ... Scanning area 18 ... Code display part 20 ... Processing device 30 ... Magnetizer 31 ... Magnetic sensor

Claims (4)

[Claims] A plurality of first magnetic elements which are randomly mixed into a scanning region of a base material and are made of a magnetically soft magnetic material having a low coercive force; A plurality of second magnetic elements made of a magnetic material having a high coercive force, and detection obtained by magnetically scanning the scanning region a plurality of times by changing the magnetization state of the second magnetic elements. A code display unit for recording data relating to a signal, wherein the object to be authenticated is checked. 2. The authenticity of an object in which a magnetically soft first magnetic element having a low coercive force and a magnetically hard second magnetic element having a high coercive force are randomly mixed in a scanning area. And a collation process for checking the object to be detected, wherein the creation process includes the steps of: A detection step of obtaining a detection signal by magnetically scanning the scanning region a plurality of times with different magnetization states, and a writing step of recording data relating to the detection signal on a code display unit; A detection step of obtaining a detection signal by magnetically scanning the scanning area a plurality of times by changing the magnetization state of the second magnetic element, and transmitting the data recorded in the code display unit. A code reading step taking, how the data is checked the authenticity of the object to be detected, characterized by comprising a determination step of the object to be detected when corresponding to the detection signal is determined to be authentic. 3. The authenticity of an object in which a magnetically soft first magnetic element having a low coercive force and a magnetically hard second magnetic element having a high coercive force are randomly mixed in a scanning area. A magnetizer capable of applying a magnetic field sufficient to magnetize the second magnetic element to the scanning area and switching magnetization conditions such as the direction and magnitude of the magnetic field. A magnetic sensor that obtains a detection signal by magnetically scanning the scanning region; and a unit that encrypts data related to the detection signal obtained by scanning the scanning region a plurality of times by switching the magnetization condition. Code writing means for recording the encrypted data on the code display portion of the detected object; reading means for reading the data recorded on the code display portion; collating the data with the detection signal; Both Apparatus for checking the authenticity of the object to be detected, characterized in that the object to be detected is provided with, means for determining as authentic when corresponding are. 4. The coercive force of the first magnetic element is H1, the coercive force of the second magnetic element is H2, the magnitude of the magnetic field of the magnetizer is B1, and the magnitude of the bias magnetic field of the magnetic sensor is B2. 4. The apparatus for checking the authenticity of an object to be detected according to claim 3, wherein H1 <B2 <H2 <B1.