JPH0754592B2 - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH0754592B2 JPH0754592B2 JP25406385A JP25406385A JPH0754592B2 JP H0754592 B2 JPH0754592 B2 JP H0754592B2 JP 25406385 A JP25406385 A JP 25406385A JP 25406385 A JP25406385 A JP 25406385A JP H0754592 B2 JPH0754592 B2 JP H0754592B2
- Authority
- JP
- Japan
- Prior art keywords
- recording medium
- magnetic
- magneto
- optical recording
- optical
- 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.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
- G11B5/58—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B13/00—Recording simultaneously or selectively by methods covered by different main groups among G11B3/00, G11B5/00, G11B7/00 and G11B9/00; Record carriers therefor not otherwise provided for; Reproducing therefrom not otherwise provided for
- G11B13/04—Recording simultaneously or selectively by methods covered by different main groups among G11B3/00, G11B5/00, G11B7/00 and G11B9/00; Record carriers therefor not otherwise provided for; Reproducing therefrom not otherwise provided for magnetically or by magnetisation and optically or by radiation, for changing or sensing optical properties
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
- Magnetic Record Carriers (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、磁気ディスク装置等において用いられる磁気
記録媒体に関するものである。TECHNICAL FIELD The present invention relates to a magnetic recording medium used in a magnetic disk device or the like.
〔従来の技術〕 従来の磁気記録媒体の構成を第５図，第６図に示す。[Prior Art] FIGS. 5 and 6 show the structure of a conventional magnetic recording medium.
第５図は長手記録用の磁気記録媒体の代表例であり、図
中１はアルミ等の非磁性基板、２はNi-P,Ni-Cu-P,Al
2O3,SiO2等の非磁性下地硬化層、３は磁化方向が媒体面
に平行な向きとなるγ−Fe2O3,Co-P,Co-Ni-P,Co-Cr等の
長手記録媒体、４はSiO2等の保護膜、５は潤滑膜であ
る。なお、保護膜４は耐食性を目的に設けられるもので
あり、従って、長手記録媒体３がN-Fe2O3のような酸化
物系の場合にはなくてもよい。FIG. 5 is a typical example of a magnetic recording medium for longitudinal recording, in which 1 is a non-magnetic substrate such as aluminum and 2 is Ni-P, Ni-Cu-P, Al.
2 O 3 , SiO 2 and other non-magnetic underlayers, and 3 is the longitudinal direction of γ-Fe 2 O 3 , Co-P, Co-Ni-P, Co-Cr, etc. whose magnetization direction is parallel to the medium surface. The recording medium, 4 is a protective film such as SiO 2 and 5 is a lubricating film. The protective film 4 is provided for the purpose of corrosion resistance, and therefore may be omitted when the longitudinal recording medium 3 is an oxide type such as N-Fe 2 O 3 .
一方、第６図は、光磁気記録用の磁気記録媒体の代表例
であり、第５図に示すものと異なるのは、長手記録媒体
３のかわりに、６で示すTb-Fe,Gd-Co,Tb-Fe-Co等の磁化
方向が媒体面に垂直となりカー効果やファラデー効果等
の磁気光学効果を示す光磁気記録媒体が設けられてい
る。On the other hand, FIG. 6 is a typical example of a magnetic recording medium for magneto-optical recording. What is different from that shown in FIG. 5 is that instead of the longitudinal recording medium 3, Tb-Fe, Gd-Co shown by 6 is shown. A magneto-optical recording medium is provided in which the magnetization direction of Tb-Fe-Co or the like is perpendicular to the medium surface and exhibits a magneto-optical effect such as a Kerr effect or a Faraday effect.
以上のような構成の磁気記録媒体を実際に磁気ディスク
装置等にて使用する場合には、１枚の両面あるいは複数
枚を一定間隔で重ねて形成される複数面の内、１面全
部、あるいは各面の一部を磁気ヘッドの位置決めに必要
となる位置決めサーボトラック用として使用している。When the magnetic recording medium having the above-mentioned configuration is actually used in a magnetic disk device or the like, one of the two surfaces or all of the plurality of surfaces formed by stacking a plurality of sheets at a constant interval, or A part of each surface is used for the positioning servo track necessary for positioning the magnetic head.
従来の磁気記録媒体は以上のように構成され、サーボ用
に使用した箇所は、サーボ用信号パターンが記録されて
本来のデータの書込み及び読出しに使用できない領域と
なるので実際の記録可能面積が減少してしまうという問
題点があった。The conventional magnetic recording medium is configured as described above, and the area used for servo is the area where the signal pattern for servo is recorded and cannot be used for original data writing and reading, so the actual recordable area is reduced. There was a problem that it did.
本発明は上記のような問題点を解消するためになされた
もので、１つの面からサーボ用信号を読出しながら同じ
面、あるいはトラック位置にデータの書込み、読出しを
可能とする磁気記録媒体を得ることを目的とする。The present invention has been made to solve the above-mentioned problems, and provides a magnetic recording medium capable of writing and reading data on the same surface or track position while reading a servo signal from one surface. The purpose is to
本発明に係る磁気記録媒体は、非磁性基板上の磁性膜
を、下層に形成された磁気光学効果を有する光磁気記録
媒体と、上層に形成された保磁力が上記光磁気記録媒体
よりも小さい長手記録媒体とから構成したものである。A magnetic recording medium according to the present invention has a magneto-optical recording medium having a magneto-optical effect formed in a lower layer of a magnetic film on a non-magnetic substrate, and a coercive force formed in an upper layer thereof is smaller than that of the magneto-optical recording medium. It is composed of a longitudinal recording medium.
本発明における磁気記録媒体においては、磁気記録され
たサーボ情報の読出しは、レーザー光等の入射光に対
し、反射光、あるいは透過光の偏光面が回転する光磁気
記録媒体の磁気光学効果（カー効果、あるいはファラデ
ー効果）を利用し、磁気記録されたデータ情報の書込
み，読出しは従来の磁気ディスク装置と同様、長手記録
媒体に対して磁気ヘッドにより行う。In the magnetic recording medium of the present invention, the reading of the magnetically recorded servo information is performed by the magneto-optical effect (curl) of the magneto-optical recording medium in which the polarization plane of reflected light or transmitted light rotates with respect to incident light such as laser light. Effect or Faraday effect), writing and reading of magnetically recorded data information is performed by a magnetic head on a longitudinal recording medium as in a conventional magnetic disk device.
以下、本発明の実施例を図について説明する。 Embodiments of the present invention will be described below with reference to the drawings.
第１図は、アルミ等の不透明な非磁性基板1aを用いた実
施例の構成を示す図で、上記非磁性基板1a上に非磁性下
地硬化層２を介して、下層側に成膜された光磁気記録媒
体６と上層側に成膜された長手記録媒体３とから成る磁
性膜７が形成され、更にその上に保護膜４と潤滑膜５が
成膜されて構成されている。上記長手記録媒体３と光磁
気記録媒体６は第５図及び第６図従来例に示したものと
同様なものである。ただし、光磁気記録媒体６の記録情
報を保存したまま長手記録媒体３への書込みを可能とす
るため，すなわち光磁気記録媒体６の保磁力以下の磁力
で長手記録媒体３への書込みを可能とするために、長手
記録媒体３としては保磁力が光磁気記録媒体６よりも小
さいものを用いる必要がある。長手記録媒体３として用
いられる各媒体の保磁力は、γ−Fe2O3が0.7KOe、Co-P
が1.0KOe、Co-Ni-Pが1.4KOe、Co-Crが0.7KOeであり、光
磁気記録媒体６として用いられる各媒体の保磁力は、Tb
-Feが5KOe、Gd-Coが1KOe、Tb-Fe-Coが10KOeであるの
で、光磁気記録媒体６としてTb-Feを用いる場合は長手
記録媒体３としてγ−Fe2O3,Co-P,Co-Ni-P,Co-Crが使用
可能であり、Gd-Coを用いる場合はγ−Fe2O3,Co-Crが使
用可能であり、Tb-Fe-Coを用いる場合はγ−Fe2O3,Co-
P,Co-Ni-P,Co-Crが使用可能である。本実施例では、光
磁気記録媒体６には保磁力が1.5KOe以上のもの，具体的
にはTb-Feを、また長手記録媒体３には保磁力が上記よ
り小さい1.2KOe以下のもの，具体的にはCo-Pを用いてい
る。FIG. 1 is a diagram showing the configuration of an embodiment using an opaque non-magnetic substrate 1a such as aluminum, which is formed on the lower side of the non-magnetic substrate 1a via a non-magnetic underlayer hardened layer 2. A magnetic film 7 composed of a magneto-optical recording medium 6 and a longitudinal recording medium 3 formed on the upper layer side is formed, and a protective film 4 and a lubricating film 5 are further formed thereon. The longitudinal recording medium 3 and the magneto-optical recording medium 6 are the same as those shown in the conventional examples of FIGS. However, since it is possible to write to the longitudinal recording medium 3 while keeping the recorded information of the magneto-optical recording medium 6, that is, it is possible to write to the longitudinal recording medium 3 with a magnetic force less than the coercive force of the magneto-optical recording medium 6. Therefore, it is necessary to use the longitudinal recording medium 3 having a coercive force smaller than that of the magneto-optical recording medium 6. The coercive force of each medium used as the longitudinal recording medium 3 is 0.7 KOe for γ-Fe 2 O 3 , Co-P
Is 1.0 KOe, Co-Ni-P is 1.4 KOe, Co-Cr is 0.7 KOe, and the coercive force of each medium used as the magneto-optical recording medium 6 is Tb.
-Fe is 5KOe, Gd-Co is 1KOe, and Tb-Fe-Co is 10KOe. Therefore, when Tb-Fe is used as the magneto-optical recording medium 6, γ-Fe 2 O 3 , Co-P is used as the longitudinal recording medium 3. , Co-Ni-P, Co-Cr can be used, when using Gd-Co γ-Fe 2 O 3 , Co-Cr can be used, when using Tb-Fe-Co γ- Fe 2 O 3 , Co-
P, Co-Ni-P, Co-Cr can be used. In this embodiment, the magneto-optical recording medium 6 has a coercive force of 1.5 KOe or more, specifically Tb-Fe, and the longitudinal recording medium 3 has a coercive force of 1.2 KOe or less, which is smaller than the above. In general, Co-P is used.
一方、第２図は、ガラス，アクリル樹脂等の透明な非磁
性基板1bを用いた他の実施例の構成を示す図で、第１図
に示した実施例と異なる点は非磁性下地硬化層２が除か
れていることと、第１図に示すものは不透明な基板1aを
使用して反射光を利用する為、該基板1aの両面に磁性膜
７を形成しても可であるが、第２図に示すものは透明な
基板1bを使用して透過光を利用する為、該基板1bの片面
にのみ磁性膜７を形成する点である。On the other hand, FIG. 2 is a diagram showing the configuration of another embodiment using a transparent non-magnetic substrate 1b made of glass, acrylic resin or the like. The difference from the embodiment shown in FIG. 2 is omitted and the one shown in FIG. 1 uses the reflected light by using the opaque substrate 1a, so that the magnetic film 7 can be formed on both surfaces of the substrate 1a. As shown in FIG. 2, the transparent substrate 1b is used to utilize the transmitted light, so that the magnetic film 7 is formed only on one surface of the substrate 1b.
以上のように構成された磁気記録媒体の使用法と動作状
況を以下に説明する。The usage and operating conditions of the magnetic recording medium configured as described above will be described below.
本発明の要点は下層に光磁気記録媒体、上層に上記より
保磁力の小さい長手記録媒体を成膜する点にあり、この
媒体を使用する磁気ディスク装置は、前記第１図，第２
図に示す各実施例に対応して夫々第３図，第４図に示す
ようになり、各実施例の媒体から成る円板8a,8bの両面
又は片面に対向する如く配置された磁気ヘッド９以外
に、サーボ情報読出しのための、全反射ミラー10,ハー
フミラー11,ポラライザ12,アナライザ13,光源14及び受
光素子（ホトダイオード）15等から成る光回路が付加さ
れている。The essential point of the present invention is that a magneto-optical recording medium is formed in the lower layer and a longitudinal recording medium having a smaller coercive force than the above is formed in the upper layer, and the magnetic disk device using this medium is shown in FIGS.
Corresponding to each embodiment shown in FIGS. 3 and 4, respectively, the magnetic head 9 is arranged so as to face both sides or one side of the disks 8a and 8b made of the medium of each embodiment. In addition, an optical circuit including a total reflection mirror 10, a half mirror 11, a polarizer 12, an analyzer 13, a light source 14, a light receiving element (photodiode) 15 and the like is added for reading servo information.
このサーボ情報書込みの方法は、まず、装置に付いてい
る磁気ヘッド９で長手記録媒体３にサーボ情報を書込
む。この状態で上面からフラッシュ光等の強い光をあ
て、光磁気記録媒体６の保磁力が０近くになる温度（キ
ュリー点）となるようにする。こうすると、長手記録媒
体３に書かれていた情報は、光磁気記録媒体６に転写さ
れる。ディスク装置における磁気ヘッド９のサーボ動作
には、この光磁気記録媒体６に転写された情報を、光源
14からのレーザー光等の入射光に対し、その反射光、あ
るいは透過光の偏光面が回転する磁気光学効果（カー効
果、あるいはファラデー効果）を利用することにより読
出して用いる。このサーボ情報の読出しを、第１図のよ
うに磁気記録媒体を構成した場合について詳しく説明す
ると、当該磁気記録媒体から成る円板8aを使用する第３
図の装置において、光源14からのレーザー光はポラライ
ザ（偏光子）12により直線偏光となりハーフミラー11を
介して円板8a上に照射される。照射された光は不透明の
非磁性基板1aにより反対面には透過せず、また反対面か
らの透過光もないので、光磁気記録媒体６からの反射光
のみが得られる。直線偏光となって照射された光の光磁
気記録媒体６からの反射光は、サーボ情報が記録された
光磁気記録媒体６における磁化反転部分（“1"）と非反
転部分（“0"）ではその偏光面の回転角が異なるため、
反射光をハーフミラー11,全反射ミラー10を介してアナ
ライザ（検光子）13に通すことにより、受光素子15を用
いてサーボ情報を読出すことができる。この情報は、該
光磁気記録媒体６がキュリー点以上に加熱されない限
り、長手記録媒体３に書かれたデータ情報により乱され
ることなく使用できる。即ち、光磁気記録媒体６にサー
ボ情報を保存したまま、長手記録媒体３は自由に磁気ヘ
ッド９による情報の書込み，読出しができることとな
る。In this method of writing servo information, first, servo information is written on the longitudinal recording medium 3 by the magnetic head 9 attached to the apparatus. In this state, strong light such as flash light is applied from the upper surface so that the coercive force of the magneto-optical recording medium 6 becomes a temperature near zero (Curie point). In this way, the information written on the longitudinal recording medium 3 is transferred to the magneto-optical recording medium 6. In the servo operation of the magnetic head 9 in the disk device, the information transferred to the magneto-optical recording medium 6 is used as a light source.
The incident light such as laser light from 14 is read and used by utilizing the magneto-optical effect (Kerr effect or Faraday effect) in which the polarization plane of the reflected light or transmitted light rotates. The reading of the servo information will be described in detail in the case where the magnetic recording medium is configured as shown in FIG. 1. The third method is to use the disk 8a made of the magnetic recording medium.
In the device shown in the figure, laser light from a light source 14 is linearly polarized by a polarizer (polarizer) 12 and radiated onto a disk 8a via a half mirror 11. Since the irradiated light is not transmitted to the opposite surface by the opaque non-magnetic substrate 1a and there is no transmitted light from the opposite surface, only the reflected light from the magneto-optical recording medium 6 can be obtained. The reflected light from the magneto-optical recording medium 6 of the linearly polarized light that is emitted is a magnetization reversal portion (“1”) and a non-reversal portion (“0”) of the magneto-optical recording medium 6 on which servo information is recorded. Then, since the rotation angle of the plane of polarization is different,
By passing the reflected light through the analyzer (analyzer) 13 via the half mirror 11 and the total reflection mirror 10, the servo information can be read using the light receiving element 15. This information can be used without being disturbed by the data information written on the longitudinal recording medium 3 as long as the magneto-optical recording medium 6 is not heated above the Curie point. That is, the longitudinal recording medium 3 can be freely written and read by the magnetic head 9 while the servo information is stored in the magneto-optical recording medium 6.
以上述べたようにこの実施例によれば、磁気記録媒体の
同一面，同一箇所に長手記録による情報と光磁気記録に
よる情報の２種の情報を記録することができる。これは
光磁気記録媒体にサーボ情報を書込み，読出しする場合
に限らず、光回路のレーザー光強度を増し、キュリー点
以上への加熱が連続的に可能なようにすれば、光磁気記
録媒体６への長手記録媒体３の情報の転写による書込み
が自由になり、データ面を２重にもつ媒体としての使用
も可能である。As described above, according to this embodiment, it is possible to record two kinds of information, that is, information by longitudinal recording and information by magneto-optical recording on the same surface and the same location of the magnetic recording medium. This is not limited to the case of writing and reading servo information on the magneto-optical recording medium, but the magneto-optical recording medium 6 can be formed by increasing the laser light intensity of the optical circuit and continuously heating it to the Curie point or higher. Writing on the longitudinal recording medium 3 by transfer of information becomes free, and the medium can be used as a medium having a double data surface.
以上のように、本発明によれば、非磁性基板上の磁性膜
を、下層に形成された磁気光学効果を有する光磁気記録
媒体と、上層に形成された保持力が上記光磁気記録媒体
よりも小さい長手記録媒体とから構成したことにより、
同一面，同一箇所に異なった方式により２種の情報を記
録することができるので、サーボ用信号等により実際の
記録可能面積が減少することのない磁気記録媒体が得ら
れるという効果がある。As described above, according to the present invention, a magneto-optical recording medium having a magneto-optical effect formed in a lower layer of a magnetic film on a non-magnetic substrate and a coercive force formed in an upper layer of the magneto-optical recording medium have Since it is composed of a small longitudinal recording medium,
Since two types of information can be recorded on the same surface and at the same location by different methods, there is an effect that a magnetic recording medium can be obtained in which the actual recordable area does not decrease due to servo signals or the like.
第１図，第２図は本発明の各実施例の構成を示す断面
図、第３図，第４図は上記第１図，第２図に示す磁気記
録媒体を使用時の装置構成を示す概略図、第５図，第６
図は夫々従来例の構成を示す断面図である。 1a,1b……非磁性基板、３……長手記録媒体、６……光
磁気記録媒体、７……磁性膜。 なお、図中同一符号は同一又は相当部分を示す。1 and 2 are cross-sectional views showing the structure of each embodiment of the present invention, and FIGS. 3 and 4 show the device structure when the magnetic recording medium shown in FIGS. 1 and 2 is used. Schematic, 5 and 6
Each of the drawings is a cross-sectional view showing the structure of a conventional example. 1a, 1b ... Non-magnetic substrate, 3 ... Longitudinal recording medium, 6 ... Magneto-optical recording medium, 7 ... Magnetic film. The same reference numerals in the drawings indicate the same or corresponding parts.
Claims (3)
記録媒体において、上記磁性膜を、下層に形成された磁
気光学効果を有する光磁気記録媒体と、上層に形成され
た保磁力が上記光磁気記録媒体よりも小さい長手記録媒
体とから構成したことを特徴とする磁気記録媒体。1. A magnetic recording medium having a magnetic film formed on a non-magnetic substrate, the magneto-optical recording medium having a magneto-optical effect formed in the lower layer, and the coercive force formed in the upper layer. And a longitudinal recording medium smaller than the above magneto-optical recording medium.
特徴とする特許請求の範囲第１項記載の磁気記録媒体。2. The magnetic recording medium according to claim 1, wherein the non-magnetic substrate is made of an opaque material.
徴と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 non-magnetic substrate is made of a transparent material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25406385A JPH0754592B2 (en) | 1985-11-13 | 1985-11-13 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25406385A JPH0754592B2 (en) | 1985-11-13 | 1985-11-13 | Magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62114142A JPS62114142A (en) | 1987-05-25 |
| JPH0754592B2 true JPH0754592B2 (en) | 1995-06-07 |
Family
ID=17259705
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25406385A Expired - Lifetime JPH0754592B2 (en) | 1985-11-13 | 1985-11-13 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0754592B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2690931B2 (en) * | 1988-03-02 | 1997-12-17 | 株式会社日立製作所 | Magneto-optical disk carrier and method for manufacturing the same |
| JPH0237546A (en) * | 1988-07-27 | 1990-02-07 | Matsushita Electric Ind Co Ltd | Magneto-optical disk and magneto-optical disk recording method |
-
1985
- 1985-11-13 JP JP25406385A patent/JPH0754592B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62114142A (en) | 1987-05-25 |
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