JPH02179902A - Magnetic recording medium and magnetic detector - Google Patents
Magnetic recording medium and magnetic detectorInfo
- Publication number
- JPH02179902A JPH02179902A JP33565188A JP33565188A JPH02179902A JP H02179902 A JPH02179902 A JP H02179902A JP 33565188 A JP33565188 A JP 33565188A JP 33565188 A JP33565188 A JP 33565188A JP H02179902 A JPH02179902 A JP H02179902A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- recording medium
- magnetic recording
- transformation
- information
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 78
- 230000009466 transformation Effects 0.000 claims abstract description 32
- 239000003302 ferromagnetic material Substances 0.000 claims abstract description 12
- 238000010884 ion-beam technique Methods 0.000 claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 5
- 229910001566 austenite Inorganic materials 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 2
- 239000000956 alloy Substances 0.000 claims description 2
- 229910000963 austenitic stainless steel Inorganic materials 0.000 claims description 2
- 230000005294 ferromagnetic effect Effects 0.000 abstract description 4
- 230000004075 alteration Effects 0.000 abstract description 2
- 230000001678 irradiating effect Effects 0.000 abstract description 2
- 230000005307 ferromagnetism Effects 0.000 abstract 1
- 230000005408 paramagnetism Effects 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 238000006243 chemical reaction Methods 0.000 description 4
- 150000002500 ions Chemical class 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000005298 paramagnetic effect Effects 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Recording Or Reproducing By Magnetic Means (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、いわゆるセキュリティが要求される用途など
において有利に実施することができる磁気記録媒体およ
び磁気検出装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording medium and a magnetic detection device that can be advantageously implemented in applications requiring so-called security.
従来の技術
典型的な先行技術では、’ｔ！ｌ！磁性材料の磁化の方
向を変化させて、２値情報の記録を行っている。Prior Art In typical prior art, 't! l! Binary information is recorded by changing the direction of magnetization of the magnetic material.
発明が解決すべき課題
このような先行技術では、磁気ヘッドなどのような磁電
変換素子を用いて、情報の書込み、読取りが可逆的に容
易であるという利点があるけれども、この反面、偽造、
情報の改宗が容易であり、高度のセキュリティを達成す
ることができないという問題がある。Problems to be Solved by the Invention Although such prior art has the advantage that it is easy to write and read information reversibly using a magneto-electric conversion element such as a magnetic head, on the other hand, it is susceptible to counterfeiting and
There is a problem that information can be easily converted and a high level of security cannot be achieved.
本発明の目的は、磁気記録情報の偽造などの改変を確実
に防ぐことができるようにした磁気記録媒体および磁気
検出装置を提供することである。An object of the present invention is to provide a magnetic recording medium and a magnetic detection device that can reliably prevent alterations such as forgery of magnetically recorded information.
課題を解決するための手段
本発明は、強磁性材料から成り、ビームの照射によって
磁気変態を生じて記録された領域を有することを特徴と
する磁気記録媒体である。Means for Solving the Problems The present invention is a magnetic recording medium characterized by being made of a ferromagnetic material and having a recording area that undergoes magnetic transformation by irradiation with a beam.
また本発明は、前記ビームは、レーザであることを特徴
とする。Further, the present invention is characterized in that the beam is a laser.
さらにまた本発明は、前記ビームは、イオンビームであ
ることを？！徴とする。Furthermore, the present invention provides that the beam is an ion beam. ! be a sign.
また本発明は、前記記録領域は、磁性層深さ方向を含む
３次元で形成されていることをｔ４徴とする。Further, in the present invention, the recording area is formed three-dimensionally including the depth direction of the magnetic layer as a t4 characteristic.
また本発明は、前記強磁性材料は、室温準安定オーステ
ナイト相を持つ鉄系合金、たとえばオーステナイトステ
ンレスであることを特徴とする。Further, the present invention is characterized in that the ferromagnetic material is an iron-based alloy having a metastable austenite phase at room temperature, such as austenitic stainless steel.
また本発明は、強磁性材料から成り、ビームの照射によ
って３次元的な磁気変態を生じて記録された領域を有す
る磁気記録媒体と、
磁電変換素子と、
磁気記録媒体と磁電変換素子とを相対的に変位する手段
とを含み、
磁電変換素子の出力によって、記録領域の３次元的な磁
気変態を検出することを特徴とする磁気検出装置である
。The present invention also provides a magnetic recording medium that is made of a ferromagnetic material and has a recording area that undergoes three-dimensional magnetic transformation by beam irradiation, a magnetoelectric transducer, and a magnetic recording medium and the magnetoelectric transducer that are placed relative to each other. A magnetic detection device is characterized in that it detects three-dimensional magnetic transformation of a recording area by the output of a magnetoelectric transducer.
作 用
本発明に従えば、磁気記録媒体は強磁性材料から成り、
レーザまたはイオンビームなどのようなビームを照射す
ることによって、磁気変態を生じて強磁性でない部分を
形成し、これによって情報を記録する。According to the present invention, the magnetic recording medium is made of a ferromagnetic material,
Irradiation with a beam such as a laser or an ion beam causes a magnetic transformation to form a non-ferromagnetic portion, thereby recording information.
このビームのエネルギを変化調節することによって、磁
気変態を生じる部分の深さを、変化して、３次元で記録
領域を形成することができる。By varying and adjusting the energy of this beam, the depth of the portion where magnetic transformation occurs can be varied to form a three-dimensional recording area.
磁気記録媒体と磁電変換素子とを相対的に変位して、前
記記録領域への磁気変態を３次元的に生じている情報を
検出する。このようにして磁気変態を生じている部分の
深さを磁電変換素子によって検出して、情報を読取るこ
とができる。このような構成を有する磁気記録媒体は、
前述の先行技術におけるように磁化方向を変化して記録
を行う構成とは全く異なっており、その記録情報の偽造
などの改変が困難である。By relatively displacing the magnetic recording medium and the magnetoelectric transducer, information in which magnetic transformation occurs three-dimensionally in the recording area is detected. In this way, the depth of the portion where magnetic transformation occurs can be detected by the magnetoelectric transducer, and information can be read. A magnetic recording medium having such a configuration is
This is completely different from the configuration in which recording is performed by changing the magnetization direction as in the prior art described above, and it is difficult to alter the recorded information such as forgery.
実施例
第１図は、本発明の一実施例の簡略化した斜視図である
。磁気記録媒体１は、たとえば薄い平板状のカードまた
は帯などであってもよく、このような磁気記録媒体は、
強磁性材料から成る。このような磁気記録媒体としては
、たとえばステンレス鋼などの材料が好適する。Embodiment FIG. 1 is a simplified perspective view of an embodiment of the present invention. The magnetic recording medium 1 may be, for example, a thin flat card or a strip.
Made of ferromagnetic material. For example, a material such as stainless steel is suitable for such a magnetic recording medium.
磁気記録媒体１が強化鋼、たとえば圧延を施されたステ
ンレス鋼５ＵＳ３０４はマルテンサイト組織を持つ強磁
性体である。このような平板状の磁気記録媒体１上に、
レーザ２を照射する。このレーザ２によって、磁気記録
媒体１上に、参照符３で示す部分に照射し、その部分３
を変態温度以上に加熱して磁気変態を生じさせる。これ
によってレーザ２が照射された部分３において結晶構造
がオーステナイト構造に変化し、強磁性から強磁性でな
い、たとえば常磁性に変化する。このようにして生じる
照射部分３の２次元平面の大きさは、レーザ２のビーム
径を絞ることによって制御することができる。その磁気
変態を生じる部分３の深さは、レーザ２のエネルギを変
化することによって、たとえば１μｍ程度以内の範囲で
制御することができる。こうしてレーザ２の径とエネル
ギとを変化して、部分３を３次元で形成することができ
る。The magnetic recording medium 1 is made of reinforced steel, such as rolled stainless steel 5US304, which is a ferromagnetic material having a martensitic structure. On such a flat magnetic recording medium 1,
Irradiate laser 2. This laser 2 irradiates the magnetic recording medium 1 to a portion indicated by reference numeral 3, and the portion 3
is heated above the transformation temperature to cause magnetic transformation. As a result, the crystal structure in the portion 3 irradiated with the laser 2 changes to an austenite structure, and changes from ferromagnetic to non-ferromagnetic, for example, paramagnetic. The size of the two-dimensional plane of the irradiated portion 3 thus generated can be controlled by narrowing down the beam diameter of the laser 2. The depth of the portion 3 where magnetic transformation occurs can be controlled, for example, within a range of about 1 μm by changing the energy of the laser 2. In this way, by changing the diameter and energy of the laser 2, the portion 3 can be formed in three dimensions.
レーザ２としては、Ａｒレーザ、Ｋ ｒレーザ、Ｎｄ
： ＹＡＧレーザ、グラスレーザ、Ｃ０２レーザ、半導
体レーザ、およびエキシマレーザなどを用いることがで
きる。このようにして、第２図に示すように、磁気変態
を生じた部分４，５．６７を形成することができる。磁
気変態を生じた部分４は、長さＬｌ、幅Ｗ１および最大
深さＤｌを有しており、その深さは、長さＬｌに沿って
変化させることができる、磁気変態を生じた部分５は、
その長さ方向が前記部分４とは異なっている。また磁気
変態を生じた部分６．７の深さＤ２．Ｄ３を調節するこ
とができる。こうして磁気変態を生じた部分４，５，６
．７と、そのような磁気変態が生じていない部分とによ
って、２値情報が記録された領域８が形成される。また
深さに対応した情報の記録を行うことができる。As the laser 2, Ar laser, Kr laser, Nd
: YAG laser, glass laser, C02 laser, semiconductor laser, excimer laser, etc. can be used. In this way, as shown in FIG. 2, the portions 4, 5.67 in which magnetic transformation has occurred can be formed. The magnetically transformed portion 4 has a length Ll, a width W1 and a maximum depth Dl, the depth of which can vary along the length Ll. teeth,
Its length direction is different from the portion 4. Also, the depth D2 of the portion 6.7 where magnetic transformation has occurred. D3 can be adjusted. Parts 4, 5, 6 where magnetic transformation occurred in this way
．． 7 and a portion where such magnetic transformation has not occurred form an area 8 in which binary information is recorded. Furthermore, information corresponding to depth can be recorded.
第３図を参照して、磁気記録媒体１の情報が記録された
領域８を走査方向９または９ａに移動させ、固定位置に
は磁電変換素子１０を設け、こうして磁気記録媒体１と
磁電変換素子１０とを相対的に変位させる。磁気記録媒
体１は、たとえばローラおよびベルトなどを用いて走査
方向９に駆動することができる。磁気変態を生じた部分
４において、その深さＤｌに対応して、磁電変換素子１
０からは第４図（１）に示されるように出力が変化する
。レベル弁別回路１１は、磁電変換素子１０の出力を、
弁別レベル１１，１１２でレベル弁別を行い、第４図（
２）および第４図（３）で示される出力を導出する。こ
うして磁気変態を生じた部分４の深さに対応した情報を
読取って再生することが可能となる。Referring to FIG. 3, the area 8 in which information is recorded on the magnetic recording medium 1 is moved in the scanning direction 9 or 9a, the magnetoelectric transducer 10 is provided at a fixed position, and the magnetic recording medium 1 and the magnetoelectric transducer are 10. The magnetic recording medium 1 can be driven in a scanning direction 9 using, for example, a roller and a belt. In the portion 4 where magnetic transformation has occurred, the magnetoelectric transducer 1 corresponds to the depth Dl.
From 0, the output changes as shown in FIG. 4 (1). The level discrimination circuit 11 converts the output of the magnetoelectric conversion element 10 into
Level discrimination is performed at discrimination levels 11 and 112, and Figure 4 (
2) and the outputs shown in FIG. 4(3) are derived. In this way, it becomes possible to read and reproduce information corresponding to the depth of the portion 4 where magnetic transformation has occurred.
磁電変換素子１０としては、磁気抵抗（略称ＭＲ）Ｔ：
子、ホール素子、およびコアにコイルを巻回して構成さ
れる磁気ヘッドなどを用いることができる。このような
磁電変換素子１ｏは、磁気変態部分４の表面形状よりも
小さい分解能を有し、その検出可能な深さがたとえば数
μｍ程度であるものを用いる。As the magnetoelectric conversion element 10, magnetoresistive (abbreviated as MR) T:
A magnetic head configured by winding a coil around a core, a Hall element, and a core can be used. Such a magnetoelectric transducer 1o has a resolution smaller than the surface shape of the magnetic transformation portion 4, and the detectable depth is, for example, about several μm.
磁気記録媒体１をＸ−Ｙステージを用いて２次元走査す
ることによって、磁気変態を生じている部分４およびそ
の他の部分の３次元パターン情報を読取ることができる
。By two-dimensionally scanning the magnetic recording medium 1 using an X-Y stage, three-dimensional pattern information of the portion 4 where magnetic transformation is occurring and other portions can be read.
本発明の他の実施例として、磁気変態を生じるために、
イオンビームを用いてもよく、その加速電圧を変化させ
て磁気変態の深さを変化させることができる。イオン種
としてＨ，ｌ−１ｅ、Ａｒ、Ｘｅ、Ｎ、Ｃ，Ｐ、Ｏ，Ｂ
、Ａｓ、Ｆｅなどを用いることができる。製造にあたっ
ては、情報を記録すべき強磁性材料から成る磁気記録媒
体上に、希望するパターンにのみイオンビームが通過す
る窓を有するマスクを作成して配置し、そのマスクの多
窓から、加速されたイオンを磁気記録媒体に注入する。In another embodiment of the invention, to produce a magnetic transformation,
An ion beam may be used, and the depth of magnetic transformation can be varied by changing its accelerating voltage. Ion species include H, l-1e, Ar, Xe, N, C, P, O, B
, As, Fe, etc. can be used. During manufacturing, a mask with windows through which the ion beam passes only in the desired pattern is created and placed on a magnetic recording medium made of ferromagnetic material on which information is to be recorded. ions are injected into the magnetic recording medium.
これによって磁気記録媒体の表面および深さ方向に希望
する磁気変態を生じさせて、希望する情報を記録するこ
とができる。This allows desired magnetic transformation to occur in the surface and depth directions of the magnetic recording medium, thereby allowing desired information to be recorded.
前記マスクを用いる代わりに、集束されたイオンビーム
を用いて、３次元の磁気変態を生じる部分を描くように
してもよい、この集束イオンビームに用いるイオン種と
しては、Ｇａ、Ｂ、ＳＬ。Instead of using the mask, a focused ion beam may be used to draw a portion that causes three-dimensional magnetic transformation.Ion species used in this focused ion beam include Ga, B, and SL.
Ａｕなどを用いることができる。Au or the like can be used.
発明の効果
以上のように本発明によれば、強磁性材料から成る磁気
記録媒体にビームを照射して磁気変態を生じて情報を記
録するようにしたので、その記録情報の改変を行うこと
は困難であり、偽造が防止され、高度のセキュリティを
要求される技術分野において、広範囲に実施することが
できる。Effects of the Invention As described above, according to the present invention, since information is recorded by irradiating a magnetic recording medium made of a ferromagnetic material to cause magnetic transformation, it is not possible to alter the recorded information. It is difficult to prevent counterfeiting, and can be widely implemented in technical fields that require a high degree of security.
第１図は本発明の一実施例の斜視図、第２図はその磁気
記録媒体ｌの斜視図、第３図は磁気記録媒体１の読取り
状態を示す斜視図、第４図は第３図に示される実施例の
動作を説明するための波形図である。
１・・・磁気記録媒体、２・・・レーザ、３，４，５６
．７・・・磁気変態部分、８・・・記録領域、９・・・
走査方向、１０・・・磁電変換素子、１１・・・処理回
路代理人 弁理士 画数 圭一部
Ｑフ
壬
手続補正書（方式）
％式％
１、事件の表示
特願昭６３−３３５６５１
、発明の名称
磁気記録媒体および磁気検出装置
３、補正をする者
事件との関係 出願人
住所 兵庫県宝塚市中山荘園４−１５
氏名高井幹夫（ばか１名）
４、代理人
住 所 大阪市西区西本町１丁目１３番３８号 新興塵
ビル国装置ＥＸ ０５２５−５９８５ ＩＮＴＡＰＴ
国際ＦＡＸ （０６）５３８−０２４７（代表）６、補
正の対象
図面および委任状
７、補正の内容
（１）図面の浄書（内容に変更なし）
（２）別紙のとおり委任状を補充する。FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a perspective view of the magnetic recording medium 1, FIG. 3 is a perspective view showing the reading state of the magnetic recording medium 1, and FIG. FIG. 3 is a waveform diagram for explaining the operation of the embodiment shown in FIG. 1... Magnetic recording medium, 2... Laser, 3, 4, 56
．． 7... Magnetic transformation portion, 8... Recording area, 9...
Scanning direction, 10...Magnetoelectric conversion element, 11...Processing circuit agent Patent attorney Number of strokes Keibu Qfuji procedural amendment (method) % formula % 1. Indication of case Patent application 1983-335651, Invention Name: Magnetic recording medium and magnetic detection device 3; Relationship with the amended person case Applicant address: 4-15 Nakayamashoen, Takarazuka City, Hyogo Prefecture Name: Mikio Takai (one idiot) 4. Agent address: 1 Nishihonmachi, Nishi-ku, Osaka City No. 13-38 Shinko Dust Building Country Equipment EX 0525-5985 INTAPT
International FAX (06) 538-0247 (Representative) 6. Drawings subject to amendment and power of attorney 7. Contents of amendment (1) Engraving of drawings (no change in content) (2) Supplement the power of attorney as shown in the attached sheet.
Claims (6)
変態を生じて記録された領域を有することを特徴とする
磁気記録媒体。(1) A magnetic recording medium characterized by being made of a ferromagnetic material and having a recording area that undergoes magnetic transformation by irradiation with a beam.
許請求の範囲第１項記載の磁気記録媒体。(2) The magnetic recording medium according to claim 1, wherein the beam is a laser.
する特許請求の範囲第１項記載の磁気記録媒体。(3) The magnetic recording medium according to claim 1, wherein the beam is an ion beam.
形成されていることを特徴とする特許請求の範囲第１項
記載の磁気記録媒体。(4) The magnetic recording medium according to claim 1, wherein the recording area is formed in three dimensions including the depth direction of the magnetic layer.
を持つ鉄系合金、たとえばオーステナイトステンレスで
あることを特徴とする特許請求の範囲第１項記載の磁気
記録媒体。(5) The magnetic recording medium according to claim 1, wherein the ferromagnetic material is an iron-based alloy having a room temperature metastable austenite phase, such as austenitic stainless steel.
元的な磁気変態を生じて記録された領域を有する磁気記
録媒体と、 磁電変換素子と、 磁気記録媒体と磁電変換素子とを相対的に変位する手段
とを含み、 磁電変換素子の出力によつて、記録領域の３次元的な磁
気変態を検出することを特徴とする磁気検出装置。(6) A magnetic recording medium made of a ferromagnetic material and having a recording area that undergoes three-dimensional magnetic transformation by beam irradiation, a magnetoelectric transducer, and a magnetic recording medium and the magnetoelectric transducer. What is claimed is: 1. A magnetic detection device comprising: a means for displacing the magnetic field;
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63335651A JP2554151B2 (en) | 1988-12-31 | 1988-12-31 | Magnetic detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63335651A JP2554151B2 (en) | 1988-12-31 | 1988-12-31 | Magnetic detection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02179902A true JPH02179902A (en) | 1990-07-12 |
| JP2554151B2 JP2554151B2 (en) | 1996-11-13 |
Family
ID=18290986
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63335651A Expired - Fee Related JP2554151B2 (en) | 1988-12-31 | 1988-12-31 | Magnetic detection device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2554151B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02198004A (en) * | 1989-01-26 | 1990-08-06 | Agency Of Ind Science & Technol | Magnetic recording method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5433041A (en) * | 1977-08-18 | 1979-03-10 | Fuji Photo Film Co Ltd | Thermal magnetic recording method |
-
1988
- 1988-12-31 JP JP63335651A patent/JP2554151B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5433041A (en) * | 1977-08-18 | 1979-03-10 | Fuji Photo Film Co Ltd | Thermal magnetic recording method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02198004A (en) * | 1989-01-26 | 1990-08-06 | Agency Of Ind Science & Technol | Magnetic recording method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2554151B2 (en) | 1996-11-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |