JP3032832B2 - Information recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium using a magnetic material having a magnetostrictive effect.

[0002]

2. Description of the Related Art Conventional portable small data storage media include an IC card having a built-in IC chip, and a magnetic card used as a telephone card. Widely used in systems. Information is written in the barcode by a combination of a black line and a space (white line) called a line code, and the information is read by a barcode reader. The bar code reader reads a line code by scanning a bar code with LED light or laser light.

[0003] The feature of the bar code system is that since a large number of labels can be produced by printing at a low cost, the running cost is extremely low. In addition, since a laser beam or the like is used, data can be read out in a non-contact manner, and a complicated shape such as a three-dimensional object can be printed and read out. On the other hand, a magnetic card is a plastic card in which a magnetic recording medium is attached, and can read and write information by magnetic recording. This feature is 0.6K
It is possible to have a capacity for recording a large amount of data as much as bits, and unlike a bar code, it can be used repeatedly by rewriting. IC
The card incorporates a semiconductor recording element and a control circuit IC in a plastic card and is driven by a small battery such as a lithium battery. The feature is that, depending on the type of the semiconductor memory element, it is possible to record a large amount of data of several tens to several hundreds of Kbytes, and it is also possible to read and write data from a position separated by, for example, 1 to 2 m by electromagnetic waves such as microwaves. There are also possible types, and their applications are expanding to various fields.

[0004]

In the case of a bar code, since the reflected light is read directly by a laser beam or the like, the light cannot be shielded between the bar code and the bar code reader. There is a drawback that when it is known, it can be easily changed and the confidentiality is low. In the case of a magnetic card, since the recording state of the magnetic storage cannot be directly seen, falsification is extremely difficult for ordinary people who cannot easily obtain a read / write device. half having advantages can measures such as increasing the encryption and security bit by utilizing, has the disadvantage that there is a possibility that the heat for a magnetic recording, data to a strong magnetic field is lost.

[0005] An object of the present invention is to provide an information recording medium having high secrecy and capable of holding recorded contents safely.

[0006]

In order to achieve this object, a recording medium according to the present invention comprises a base, an amorphous metal tag of an amorphous metal foil or an amorphous metal fiber disposed on the base, and an amorphous metal tag. The amorphous metal layer is made of a material having high magnetic permeability and a magnetostrictive effect. Furthermore, by subjecting a portion of the amorphous metal to an annealing process, a portion having changed magnetic permeability and magnetostrictive effect characteristics is provided, and a portion which has been processed and a portion which has not been processed correspond to binary digital values to be recorded. It is configured to store information. Reading stored information from the information recording medium of the present application includes an excitation coil for magnetically exciting the amorphous metal layer, and a detection magnetic head for detecting a magnetic change based on the excitation of the amorphous metal layer. Can be carried out by using an apparatus.

[0007]

According to the present invention, any information can be recorded on the information recording medium. When recording information on this recording medium,
A part of the amorphous metal is annealed by laser, microwave, current or the like to change physical properties as a magnetic material. Also, the recorded amorphous metal layer is
Since the cover is covered with the cover layer, it is possible to provide a recording information medium that is difficult or difficult to falsify.
Further, since the crystal structure of the amorphous metal layer is changed by high-temperature processing, information is not lost due to magnetism, heat and temperature in a normal use range, and semi-permanent recording becomes possible. Next, in the information reading device, the information stored in the recording information medium can be read safely and reliably by using the excitation coil and the detection magnetic head.

[0008]

Next, an information recording medium and an information reading apparatus according to an embodiment of the present invention will be described with reference to the drawings. 1 and 2 show an unrecorded information recording medium 1. The information recording medium 1 includes an insulating opaque substrate 2 such as plastic or paper as a base, a rectangular (tag-shaped) amorphous metal layer 3 disposed on the surface as a data carrier, and a plastic or paper. And a cover layer 4 of an insulating, non-magnetic and opaque material. The amorphous metal layer 3 is made of an amorphous magnetic material having a high magnetic permeability and a magnetostrictive effect, that is, an amorphous metal.

FIG. 3 shows a pattern change of the amorphous metal layer 3 of the recorded information recording medium 1. Amorphous part 5
Is the same as the unrecorded pattern, but the crystallized portion 6 is a portion in which the physical structure of the amorphous metal has changed during the annealing process. Due to this structural change, a metal structure called an amorphous state is changed to a crystalline state usually found in a metal, and the high magnetic permeability and the magnetostrictive effect of the amorphous metal are reduced. The relationship between binary data consisting of logical “0” and “1” and the pattern of the amorphous metal layer 3 is, for example, “0” in the amorphous state portion,
The crystal part after the annealing treatment is set to “1”. Of course, it is possible to correspond to the opposite state. Annealing processing corresponding to data writing of the amorphous metal layer 3 as a data carrier is realized by selecting a portion to be crystallized and irradiating a laser beam having a high output or irradiating a microwave having a high output. can do.

In the example shown in FIG. 4, after the amorphous metal layer 3 is selectively annealed and information is written, the cover layer 4 made of a non-magnetic material is formed.
Is covered on the substrate 1 and the amorphous metal layer 3.
Since the amorphous metal layer 3 as a data carrier of the completed recorded information recording medium 1 is covered with the cover layer 4 made of a non-magnetic material, erroneous erasure of information or intentional change can be prevented.

FIG. 5 shows an example of a reading apparatus. The magnetic head of the reader has a magnetic head for detection 8 and an excitation coil 9 arranged opposite to each other at a predetermined distance from the amorphous metal tag 3 so as to sandwich the information recording medium 1. Is excited magnetically. A magnetic head 8 for detection corresponds to the surface of the excited amorphous metal layer 3, a detection circuit 7 is connected to the magnetic head 8 for detection, and a signal processing circuit such as a microprocessor (not shown) is connected to the detection circuit 7. Is connected. An excitation power supply 10 is connected to the excitation coil 9.

FIG. 6 shows general magnetization characteristics of an amorphous metal layer. The magnetization characteristics of the portion where the annealing process has not been performed are square as shown in FIG. Therefore, when an external magnetic field sufficient to create a magnetic saturation state is applied, a pulse signal is detected at the saturation excess point 11 by the large Barkhausen effect. FIG. 6B shows the magnetization characteristics of a portion of the amorphous metal layer where the annealing process is performed.
No square magnetism characteristic peculiar to an amorphous metal is observed, and the curve becomes a gentle curve seen in ordinary iron ferrite or the like, and a pulse due to the large Barkhausen effect is not detected.

FIG. 7C shows a waveform detected by the detection head 8 when a magnetic field is changed by the excitation coil 9 in an unwritten portion of the amorphous metal layer 3 where the annealing process is not performed. At the magnetic saturation transition point, a pulse signal unique to the Barkhausen effect is detected by being superimposed on the excitation signal. FIG. 7D shows a detection signal waveform of a portion where the annealing process has been performed, and the pulse signal processing is not performed or is extremely small.

FIG. 8 shows an example of a waveform detected by scanning the surface of the information recording medium 1 at the position of the amorphous metal tag 3 on which information is written by the excitation coil 9 and the magnetic head 8 for detection. The presence / absence of the annealing process corresponds to the presence / absence of the pulse signal, and can be determined as binary information.

The information reading from the recording medium according to the present invention is not limited to the above-mentioned example, but can be modified. For example, in reading information from a storage medium,
Amorphous metal layer 3
A method of detecting a change in magnetic permeability may be used. In this case, the magnetic coupling coefficient changes due to the change in the magnetic permeability, and appears as a difference in the signal detection level in the magnetic head for detection.

[0016]

As described above, an information recording medium that can be easily recorded can be manufactured at low cost by partially performing the annealing process according to the present invention and changing the processing properties as a magnetic material. Further, since the recorded amorphous metal layer tag is covered with the cover, it cannot be seen, making it difficult to falsify, and it is possible to provide an information recording medium with high data security. In addition, since information is stored by annealing, strong recording in an external use environment is possible. Also,
The recorded contents can be read stably and reliably.

[Brief description of the drawings]

FIG. 1 is a plan view showing a surface of an information recording medium before writing according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an information recording medium according to the present invention after completion of providing a cover layer on a substrate.

FIG. 3 is a plan view showing the surface of the information recording medium according to the present invention after writing.

FIG. 4 is a perspective view showing a state in which a cover layer is provided on a substrate when producing the information recording medium of the present invention.

FIG. 5 is a block diagram showing a reading device for reading information from an information recording medium according to the present invention.

FIG. 6 shows magnetization characteristics of an amorphous metal.

FIG. 7 is a detection signal from an information recording medium according to the present invention.

FIG. 8 shows a detection signal when recording information is continuously read from a written information recording medium according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Information recording medium 2 Substrate 3 Amorphous metal tag 4 Cover layer 5 Amorphous part 6 Crystallized part 7 Detection circuit 8 Magnetic head for detection 9 Excitation coil 10 Power supply for excitation 11 Saturation transient point

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Atsumi Nishi 1-41 Kugayama, Suginami-ku, Tokyo Iwasaki Communication Equipment Co., Ltd. (56) References JP-A-61-107488 (JP, A) ( 58) Field surveyed (Int.Cl. ⁷ , DB name) B42D 15/10 501 G06K 19/06 G11B 5/80

Claims (1)

(57) [Claims] 1. A substrate made of an insulative opaque material, and disposed on the substrate in a strip shape and partially crystallized by annealing.
Binary data is composed of the metallized part and the untreated part.
Wherein comprising a magnetic layer made of amorphous material formed so as to formed, and a magnetic body layer overlying magnetic material layer is disposed on the substrate so as not to be visually confirmed insulating opaque cover layer An information recording medium using a magnetic layer as a digital information recording unit .