JP2579964B2 - Recording method - Google Patents
Recording methodInfo
- Publication number
- JP2579964B2 JP2579964B2 JP62275637A JP27563787A JP2579964B2 JP 2579964 B2 JP2579964 B2 JP 2579964B2 JP 62275637 A JP62275637 A JP 62275637A JP 27563787 A JP27563787 A JP 27563787A JP 2579964 B2 JP2579964 B2 JP 2579964B2
- Authority
- JP
- Japan
- Prior art keywords
- recording
- bit
- information
- magneto
- pulse
- 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 - Fee Related
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
- G11B11/10502—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing characterised by the transducing operation to be executed
- G11B11/10517—Overwriting or erasing
- G11B11/10519—Direct overwriting, i.e. performing erasing and recording using the same transducing means
- G11B11/10521—Direct overwriting, i.e. performing erasing and recording using the same transducing means using a single light spot
Landscapes
- Optical Recording Or Reproduction (AREA)
- Recording Or Reproducing By Magnetic Means (AREA)
Description
【発明の詳細な説明】 〔概 要〕 光磁気ディスクにおいて情報の記録を重ね書きで行う
方法に関し、 重ね書きを容易にかつ高速で行い得るようにするこを
目的とし、 新しい記録ビットを形成すべき部分以外の部分におい
て、記録ビットの形成に用いられるものよりも幅の狭い
光パルスの連続からなる消去ビームを照射するように、
構成する。DETAILED DESCRIPTION OF THE INVENTION [Overview] Regarding a method for recording information on a magneto-optical disk by overwriting, a new recording bit is formed for the purpose of enabling overwriting to be performed easily and at high speed. In a part other than the power part, so as to irradiate an erasing beam consisting of a continuous light pulse narrower than that used for forming the recording bit,
Configure.
本発明は記録方法に関し、さらに詳しく述べると、光
磁気ディスクにおいて情報の記録を重ね書きで行う方法
に関する。The present invention relates to a recording method, and more particularly, to a method for recording information on a magneto-optical disk by overwriting.
従来の光磁気ディスクでは、通常、次のようにして情
報の記録、再生及び消去が行われている： 記録…磁化の方向が一方向にそろえられたディスクの記
録媒体に高出力のレーザービームを照射してキュリー温
度又は補償温度以上に加熱し、外部磁界によって、レー
ザ照射部だけの磁化方向を外部磁界の方向と同じとす
る。なお、この情報記録はレーザ強度を変調して行う。In a conventional magneto-optical disk, information is recorded, reproduced, and erased in the following manner: Recording: A high-power laser beam is applied to a recording medium of a disk whose magnetization direction is aligned in one direction. Irradiation heats the Curie temperature or the compensation temperature or higher, and the magnetization direction of only the laser irradiated portion is made to be the same as the direction of the external magnetic field by the external magnetic field. This information recording is performed by modulating the laser intensity.
再生…低出力のレーザービームを記録媒体に照射して、
磁気的カー効果による反射光の偏光面の回転方向で、記
録符号“0",“1"を読み取る。Reproduction: A low-power laser beam is applied to the recording medium,
The recording codes "0" and "1" are read in the direction of rotation of the plane of polarization of the reflected light due to the magnetic Kerr effect.
消去…高出力のレーザービームを記録媒体に照射して、
記録とは逆方向の外部磁界によって、磁化の方向をもと
に戻す。Erase: Irradiate the recording medium with a high-power laser beam,
The direction of magnetization is restored by an external magnetic field in the direction opposite to the recording.
この従来の情報記録方法では、高出力のレーザビーム
を照射した部分のみにおいて記録媒体の磁化の方向が変
化するので、一度記録された情報を新たな情報に書き換
えるには、一旦旧情報を消去してから新情報を書き込ま
なければならない。したがって、情報の書き換えにはデ
ィスクを最低２回転させることが必要であり、そのぶん
だけ情報書き込み速度が遅くなる。In this conventional information recording method, the direction of magnetization of the recording medium changes only in a portion irradiated with a high-power laser beam. Therefore, in order to rewrite information once recorded with new information, the old information must be erased once. Before writing new information. Therefore, it is necessary to rotate the disk at least two times to rewrite the information, and the information writing speed is reduced by that much.
情報書き込み速度の高速化のため、いくつかの重ね書
き（オーバーライト）の方法が提案されている。例え
ば、Appl,Phys,Lett.49（８）473,1986には、反磁界を
利用して情報の記録及び消去を行う方法が提案されてい
る。この方法によれば、消去する場合、書いてあるビッ
トがあるか否かをみながら、もしも書いてあれば、その
書いてあるビットの中心に消去ビームをあててこれを消
去し、もしも書いてなければ何もせず、一方、記録する
場合、同じく書いてあるビットがあるか否かをみなが
ら、もしもビットがなければ新たにビットを書き込み、
もしもすでにビットがあれば何もしないことによって、
オーバーライトを行う。この方法を第３図を参照しなが
ら説明すると、図の（Ａ）は既存の、すなわちすでに書
いてある記録ビットの分布を示し、（Ｂ）は新たに記録
しようとするビットの分布を示し、そして（Ｃ）は実際
に照射されるビームのパルス波形を示す。図から、既存
ビットの除去にはそのビットの中心に弱い（但し、再生
パルスよりは大）消去パルス11をあて、既存ビットをそ
のまま新ビットに引き継ぐ場合には何もせず、そして新
ビットを形成するためには強い記録パルス12をあてるこ
とが理解されるであろう。ここで、既存ビットは、記録
ビームに先行する別の光ビームで読み出すのが一般的で
ある。なお、既存ビットの除去に当ってそのビットの中
心のみに弱いパルスをあてるのは、すでに形成されてい
るバブルの中心部にもう１つの小さなバブルができ、こ
れらのバブルが互いに作用しあってビットが消失するか
らである。In order to increase the information writing speed, several overwriting methods have been proposed. For example, Appl, Phys, Lett. 49 (8) 473, 1986 proposes a method for recording and erasing information using a demagnetizing field. According to this method, when erasing, it is checked whether there is a written bit, and if it is written, an erase beam is applied to the center of the written bit to erase it, and if it is written, If there is no bit, if there is no bit, a new bit is written.
By doing nothing if there are already bits,
Perform overwriting. This method will be described with reference to FIG. 3. In FIG. 3, (A) shows the distribution of existing, that is, already written, recording bits, (B) shows the distribution of bits to be newly recorded, (C) shows the pulse waveform of the beam actually irradiated. As shown in the figure, the existing bit is removed by applying a weak (but larger than the reproduction pulse) erasing pulse 11 to the center of the bit, doing nothing when the existing bit is taken over as the new bit, and forming the new bit. It will be understood that a strong recording pulse 12 is applied to perform this. Here, the existing bits are generally read by another light beam preceding the recording beam. The reason why a weak pulse is applied only to the center of the existing bit to remove the existing bit is that another small bubble is formed at the center of the already formed bubble, and these bubbles interact with each other to form a bit. Is lost.
従来の技術の項において第３図を参照して説明したオ
ーバーライトの方法は、光磁気ディスクの高速化のため
に非常に有効な手段であると考えられる。この方法は、
しかし、情報の書き換えを行う前に、すでに書き込まれ
ている情報の位置を正確に検出しなければならないとい
う問題点を有する。このような位置の検出は煩雑であ
り、時間がかかり、また、実際に位置ずれがあった場合
には、正しい書き換えを行うことが不可能である。The overwriting method described with reference to FIG. 3 in the section of the prior art is considered to be a very effective means for increasing the speed of a magneto-optical disk. This method
However, there is a problem that the position of the already written information must be accurately detected before the information is rewritten. Such position detection is complicated and time-consuming, and it is not possible to perform correct rewriting when there is an actual positional deviation.
本発明の目的は、光磁気ディスクにおいて情報の記録
を重ね書きで行うに当って、重ね書きを容易にかつ高速
で行い得るようにすることにある。An object of the present invention is to enable overwriting to be performed easily and at high speed in recording information on a magneto-optical disk by overwriting.
上記した目的は、本発明によれば、光磁気ディスクに
おいて情報の記録を重ね書きで行う方法であって、前記
光磁気ディスクの記録層のうちの新しい記録ビットを形
成すべき部分以外の部分において、記録ビットの形成に
用いられるものよりも幅の狭い光パルスの連続からなる
消去ビームを照射しかつ、その際、前記消去ビームの光
パルスの周波数を記録ビットの形成に用いられる光パル
スの最高周波数よりも大とすることを特徴とする記録方
法によって達成することができる。According to the present invention, there is provided a method for recording information on a magneto-optical disk by overwriting, wherein a portion other than a portion where a new recording bit is to be formed in a recording layer of the magneto-optical disk. Irradiating an erasing beam consisting of a succession of light pulses narrower than that used to form the recording bit, and at this time, adjusting the frequency of the light pulse of the erasing beam to the highest of the light pulse used to form the recording bit. This can be achieved by a recording method characterized in that the frequency is higher than the frequency.
この本発明方法を第１図を参照しながら説明する。図
の（Ａ）及び（Ｂ）は、本発明のより完全な理解のた
め、第３図の（Ａ）及び（Ｂ）に同じくしてある。図の
（Ｃ）から理解されるように、本発明方法では、新ビッ
トを形成すべき個所以外の部分に細い消去パルス１をパ
ルス間隔をせまくして連続的に照射し、かつ記録部分に
は記録パルス２を照射する。消去パルス１及び記録パル
ス２の高さは、図示のように異なってもよく、あるいは
同一であってもよい。This method of the present invention will be described with reference to FIG. FIGS. 3A and 3B are identical to FIGS. 3A and 3B for a more complete understanding of the present invention. As can be understood from FIG. 2C, in the method of the present invention, a portion other than the portion where a new bit is to be formed is continuously irradiated with a narrow erasing pulse 1 with a narrower pulse interval, and a recording portion is provided. The recording pulse 2 is irradiated. The heights of the erase pulse 1 and the recording pulse 2 may be different as shown, or may be the same.
本発明方法では、消去ビームとして、より幅の狭いパ
ルスを多数照射することで、既存ビットの有無にかかわ
らず消去を実式し、かつ必要な個所では記録を実施する
ことで、既存ビットがどのようであれ、新しい情報を直
接的に重ね書きすることができ、また、従来のような先
行ビームとの位置調整等の問題がない。また、本発明者
らの知見によれば、消去を確実に実施するためには、消
去ビームの光パルスの周波数が記録ビットの形成に用い
られる光パルスの最高周波数の３倍以上であることが好
ましい。In the method of the present invention, by irradiating a large number of narrower pulses as an erasing beam, erasing is performed irrespective of the presence or absence of existing bits, and recording is performed where necessary, so that the existing bits can be determined. In any case, new information can be directly overwritten, and there is no problem such as the conventional position adjustment with the preceding beam. Further, according to the knowledge of the present inventors, in order to perform erasure reliably, the frequency of the light pulse of the erasing beam should be at least three times the highest frequency of the light pulse used to form the recording bit. preferable.
本発明方法を実施するに当って、この技術分野におい
て公知な光磁気ディスクを任意に使用することができ
る。一例を示すと、基板としてガラス基板を使用し、こ
の基板上にプリグルーブパターンが形成された紫外線硬
化樹脂（いわゆるフォトポリマー）やポリメチルメタク
リレート、ポリカーボネートなどの有機樹脂からなるプ
リグルーブパターン層を配置する。さらに、この層上に
は光磁気記録媒体層を配置する。この層は、特性にすぐ
れているばかりでなく、スパッタ法や蒸着法による成膜
が可能であり、媒体の大面積化が容易であるので、希土
類−遷移金属アモルファス合金から形成するのが有利で
ある。しかし、必要に応じて、その他の媒体材料、例え
ばMnBi,MnCuBiなどの多結晶性材料、ガーネット系単結
晶材料などから形成してもよい。In carrying out the method of the present invention, any magneto-optical disk known in the art can be used. As an example, a glass substrate is used as a substrate, and a pre-groove pattern layer made of an organic resin such as an ultraviolet curable resin (a so-called photopolymer) having a pre-groove pattern formed thereon, polymethyl methacrylate, or polycarbonate is disposed on the substrate. I do. Further, a magneto-optical recording medium layer is disposed on this layer. This layer is not only excellent in characteristics, but also can be formed by a sputtering method or a vapor deposition method, and the area of the medium can be easily increased. Therefore, it is advantageous to form the layer from a rare earth-transition metal amorphous alloy. is there. However, if necessary, it may be formed from another medium material, for example, a polycrystalline material such as MnBi or MnCuBi, or a garnet-based single crystal material.
プリグルーブパターン層と記録媒体層の中間には、前
者の層中の水分やモノマーの作用から記録媒体層を守る
ため、屡々下地とも呼ばれる保護膜を介在させるのが好
ましい。この保護膜は、例えば、SiO2,TiO2,ZnS,AlN,Si
3N4などの材料から形成することができる。さらに、こ
の保護膜と同様の材料からなる保護膜を、記録媒体層４
の上方に形成するのが好ましい。この上方の保護膜は、
外気中の水分等の影響から記録媒体層を保護するのに有
効である。In order to protect the recording medium layer from the action of moisture and monomers in the former layer, it is preferable to interpose a protective film often called an underlayer between the pre-groove pattern layer and the recording medium layer. This protective film is made of, for example, SiO 2 , TiO 2 , ZnS, AlN, Si
It can be formed from materials such as 3 N 4. Further, a protective film made of the same material as the protective film is formed on the recording medium layer 4.
It is preferred to form above. The protective film above this
This is effective for protecting the recording medium layer from the influence of moisture or the like in the outside air.
上記したような光磁気ディスクは、同じくこの技術分
野において公知な任意のディスク装置の変更により、例
えばLD変調回路の導入により、情報の重ね書きをするこ
とができる。The above-described magneto-optical disk can be overwritten with information by changing any disk device that is also known in this technical field, for example, by introducing an LD modulation circuit.
本発明では、既存ビットの消去個所に限って消去する
のではなくて、より幅の狭いパルスを多数間断なくかけ
つづけるので、位置精度とは無関係に既存ビットを消去
することができる。According to the present invention, not only the erasure of the existing bit is performed but also a plurality of narrower pulses are continuously applied without interruption, so that the existing bit can be erased regardless of the positional accuracy.
グルーブ付きのガラス基板を用意し、これにTb24Fe68
Co8を膜厚100nmでスパッタ成膜して記録層とした。Prepare a glass substrate with a groove, and add Tb 24 Fe 68
Co 8 was formed into a recording layer by sputtering to a thickness of 100 nm.
得られた光磁気ディスクを使用して、ビット間隔２μ
ｍ、外部磁場なし、ディスク回転速度10m/sec、記録パ
ワー5mWの条件の下で通常の記録を実施した。C/N比＝43
dBが得られた。Using the obtained magneto-optical disk, a bit interval of 2 μm was used.
Normal recording was performed under the following conditions: m, no external magnetic field, disk rotation speed 10 m / sec, and recording power 5 mW. C / N ratio = 43
dB was obtained.
引き続いて、上記のようにして記録した情報の上に、
ビットの大きさ１μｍ、ビット間隔３μｍで情報の重ね
書きを行い、その際、書き込みパルスの間を短い光パル
スの繰り返し（ビット長にして0.2μｍのパルス幅）で
充填した。満足し得るオーバーライトが可能であり、C/
N比＝45dB、前歴としての３ビット間隔２μｍの信号成
分の減衰＝−34dBが得られた。Subsequently, on the information recorded as above,
Information was overwritten at a bit size of 1 μm and a bit interval of 3 μm. At that time, a short light pulse was repeated between write pulses (a pulse width of 0.2 μm in bit length). Satisfactory overwriting is possible and C /
The N ratio = 45 dB and the attenuation of the signal component with a 3-bit interval of 2 μm = −34 dB as the previous history were obtained.
第２図は、上記のような結果をまとめた記録特性のグ
ラフであり、曲線Ｉはビット長１μｍ（周波数2.4MHz）
のものを、曲線IIはビット長0.4μｍ（12MHz）のもの
を、それぞれ示す。ビット長0.4μｍ（12MHz）での記録
特性を見ると、記録パワー約4.8mW以下では記録できな
い。しかし、記録されている信号は消去することができ
ていることがわかる。FIG. 2 is a graph of recording characteristics summarizing the above results. Curve I shows a bit length of 1 μm (frequency of 2.4 MHz).
, And curve II shows that of a bit length of 0.4 μm (12 MHz). Looking at the recording characteristics at a bit length of 0.4 μm (12 MHz), recording cannot be performed with a recording power of about 4.8 mW or less. However, it can be seen that the recorded signal can be erased.
本発明によれば、光磁気記録時に、１ビームヘッドで
のオーバーライトを容易かつ高速で行うことができる。According to the present invention, overwriting with a one-beam head can be performed easily and at high speed during magneto-optical recording.
第１図は、本発明の記録方法を示した略示図、 第２図は、本発明の光磁気記録の記録特性を示したグラ
フ、そして 第３図は、従来の記録方法を示した略示図である。 図中、１は消去パルス及び２は記録パルスである。1 is a schematic diagram showing a recording method of the present invention, FIG. 2 is a graph showing recording characteristics of magneto-optical recording of the present invention, and FIG. 3 is a schematic diagram showing a conventional recording method. FIG. In the figure, 1 is an erasing pulse and 2 is a recording pulse.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 伊藤 健一 神奈川県川崎市中原区上小田中1015番地 富士通株式会社内 (72)発明者 小川 清也 神奈川県川崎市中原区上小田中1015番地 富士通株式会社内 (56)参考文献 特開 昭61−190740（ＪＰ，Ａ) ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Kenichi Ito 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Seiya Ogawa 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Fujitsu Limited (56) References JP-A-61-190740 (JP, A)
Claims (1)
書きで行う方法であって、前記光磁気ディスクの記録層
のうちの新しい記録ビットを形成すべき部分以外の部分
において、記録ビットの形成に用いられるものよりも幅
の狭い光パルスの連続からなる消去ビームを照射しか
つ、その際、前記消去ビームの光パルスの周波数を記録
ビットの形成に用いられる光パルスの最高周波数よりも
大とすることを特徴とする記録方法。1. A method for recording information on a magneto-optical disk by overwriting, wherein a recording bit is formed in a portion of a recording layer of the magneto-optical disk other than a portion where a new recording bit is to be formed. Irradiating an erasing beam consisting of a succession of light pulses narrower than that used, wherein the frequency of the light pulse of the erasing beam is greater than the highest frequency of the light pulse used to form the recording bits; A recording method characterized in that:
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62275637A JP2579964B2 (en) | 1987-11-02 | 1987-11-02 | Recording method |
| EP88310274A EP0315415B1 (en) | 1987-11-02 | 1988-11-01 | Overwriting information in magneto-optical memory |
| DE88310274T DE3883349T2 (en) | 1987-11-02 | 1988-11-01 | Simultaneous deletion and rewriting of information in a magneto-optical memory. |
| KR1019880014323A KR920003781B1 (en) | 1987-11-02 | 1988-11-01 | Magneto-optical overwriting method |
| US07/476,588 US5353265A (en) | 1987-11-02 | 1990-02-07 | Magneto optical overwriting methods using a single optical head designed for a two-beam overwrite |
| US07/655,027 US5144601A (en) | 1987-11-02 | 1991-02-14 | Magneto-optical overwriting methods using erasing pulses, each of which has a higher frequency and narrower width than that of the overwriting pulses |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62275637A JP2579964B2 (en) | 1987-11-02 | 1987-11-02 | Recording method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01119941A JPH01119941A (en) | 1989-05-12 |
| JP2579964B2 true JP2579964B2 (en) | 1997-02-12 |
Family
ID=17558235
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62275637A Expired - Fee Related JP2579964B2 (en) | 1987-11-02 | 1987-11-02 | Recording method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2579964B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2020243C (en) * | 1989-06-30 | 1994-12-13 | Eiji Ohno | Optical information recording method and recording apparatus |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0721893B2 (en) * | 1985-02-19 | 1995-03-08 | 日本電気株式会社 | Magneto-optical recording method |
-
1987
- 1987-11-02 JP JP62275637A patent/JP2579964B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01119941A (en) | 1989-05-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |