JPS6025004A - Opto-magnetic recording device - Google Patents
Opto-magnetic recording deviceInfo
- Publication number
- JPS6025004A JPS6025004A JP13249483A JP13249483A JPS6025004A JP S6025004 A JPS6025004 A JP S6025004A JP 13249483 A JP13249483 A JP 13249483A JP 13249483 A JP13249483 A JP 13249483A JP S6025004 A JPS6025004 A JP S6025004A
- Authority
- JP
- Japan
- Prior art keywords
- waveform
- output
- signal
- recording device
- put together
- 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.)
- Pending
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
-
- 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
- G11B5/02—Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
Abstract
Description
【発明の詳細な説明】
この発明は特にレーザを用いた高密度光磁気記録装置に
関する。DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a high-density magneto-optical recording device using a laser.
この装置においては、移動する記録媒体の加熱がレーザ
ビームで行なわれるので、媒体上の一定点の温度上昇は
比較的ゆっくりと上り下るので、ディジタル記録におい
ては残留磁気は空間的な確率曲線的な形となる。そこで
、逐次密接した記録を行なうと重なり部が生じ、高密度
化を妨げる。In this device, the moving recording medium is heated by a laser beam, so the temperature rise at a certain point on the medium rises and falls relatively slowly. It takes shape. Therefore, if recording is performed closely one after another, overlapping portions will occur, which will prevent high density.
本発明は信号波形を時間的に適当に変形して局部の熱の
立上りを速くかつ立下りも速かにすることによって、実
質上記録磁化の分布を方形的に近ずけ、より高密度化を
可能にすることを要旨とする。The present invention makes the distribution of recorded magnetization substantially rectangular by appropriately changing the signal waveform temporally to make the local heat rise faster and fall faster, thereby achieving higher density. The purpose is to make it possible.
第１図は本発明の適用される発明者出願特願昭５８−２
５３８９号明細書記載の如き光磁気記録装置を示す。１
は磁性媒体で右へ進む。２は一方向磁化用磁石で、３は
これと逆方向磁化磁石であって、３は弱いものでよい。Figure 1 shows the inventor's patent application No. 58-2 to which the present invention is applied.
A magneto-optical recording device as described in No. 5389 is shown. 1
moves to the right in a magnetic medium. 2 is a magnet for unidirectional magnetization, and 3 is a magnet for magnetization in the opposite direction, and 3 may be a weak magnet.
°４は半導体レーザで、信号７で変調されレンズ５でビ
ーム６を生じ３の所でスポットを生じる。磁石３はビー
ム側でもよい。4 is a semiconductor laser, which is modulated by a signal 7 to produce a beam 6 through a lens 5 and a spot at 3; The magnet 3 may be on the beam side.
第２図は周知の光磁気記録装置の例で、信号はコイルや
ヘッド３に入り、レーザ４は一定ビームを生じる。FIG. 2 is an example of a well-known magneto-optical recording device in which the signal enters a coil or head 3 and a laser 4 produces a constant beam.
何れにしても、テープ局部の微少区間の温度変化は急昇
急降できない。In any case, the temperature change in a small local area of the tape cannot rise or fall suddenly.
第３図はテープ方形波的信号に対し進行方向Ｘに関する
ある瞬間の温度分布を示す。熱の伝導率の比熱、従フて
熱時定数によって図の如き確率曲線的な裾を引いた形と
なることは明らかである。FIG. 3 shows the temperature distribution at a certain instant in the traveling direction X for a tape square wave signal. It is clear that the specific heat of the thermal conductivity and the thermal time constant form a probability curve with a tail as shown in the figure.
従って記録された残留磁気も同様な形となり、ディジタ
ルの例えば「１」の信号の境界が明確でなくなる。Therefore, the recorded residual magnetism has a similar shape, and the boundaries of digital signals, such as "1", are no longer clear.
第４図は第３図に示すような記録が連フた場合を示し、
１６．１６．１７．１８は逐次の磁化を示す。図示のよ
うに隣接の磁化がオーバーラツプして混信するか、低密
度化するかを選ばざるを得ない。換言すれば、帯域制限
が速かに生じ得ない。Figure 4 shows a case where the records shown in Figure 3 are continuous,
16.16.17.18 show sequential magnetization. As shown in the figure, there is no choice but to choose between overlapping adjacent magnetizations and interference, or reducing the density. In other words, band limitation cannot occur quickly.
第５図は第４図の磁化分布を改善して方形に近ずけた場
合を示し、図示の如＜１５’、１Ｂ’、１７’、１Ｂ’
のように高密度化できることが判る。FIG. 5 shows the case where the magnetization distribution in FIG. 4 has been improved to approach a rectangular shape.
It can be seen that the density can be increased as shown in the figure.
第６図は第５図に示す如き磁化分布を生じる本発明回路
を示す。信号７は２ｏでディジタル化され、２５のよう
な方形波列を生じるが、更に２１で２６に示すように変
形される。これは周知の如き非線形処理あるいは微分回
路等を用いて実行できる、２６のような波形を例えば第
１図のレーザ４に用いれば最初は強力に局部加熱して波
形の立上りを速かにし、立下りも改善できる。２６の波
形はシヱミーションで最適化することができ、第３図の
１０の分布を最も隣接混信の少ないよう選ぶことは容易
である。FIG. 6 shows a circuit according to the invention which produces a magnetization distribution as shown in FIG. Signal 7 is digitized at 2o, yielding a square wave train such as 25, but is further transformed at 21 as shown at 26. This can be done using well-known nonlinear processing or a differential circuit.If a waveform such as 26 is used, for example, in the laser 4 in FIG. The descent can also be improved. 26 waveforms can be optimized by simulation, and it is easy to select the 10 distributions in FIG. 3 to minimize adjacent interference.
第７図は第６図の２１の内容例で、第６図２０の出力は
微分回路３０の出力と合成し、１ビツトパルス遅延３２
を経て振幅を調節した微分出力を３３で再び合成して得
られる。その他種々の周知の波形変換回路を用いること
ができる。FIG. 7 is an example of the contents of 21 in FIG. 6. The output of 20 in FIG.
The amplitude-adjusted differential outputs are synthesized again at 33. Various other known waveform conversion circuits can be used.
本発明装置は上記の如く記録密度を向上するのみならず
、レーザの過大な出力を不要とし長寿命化できる。これ
は局部的加熱を効率良く行い得るからである。The device of the present invention not only improves the recording density as described above, but also eliminates the need for excessive laser output and can extend the life of the device. This is because local heating can be performed efficiently.
本発明は上記特定例に限らず、種々の変形が可能である
。The present invention is not limited to the above-mentioned specific example, and various modifications are possible.
第１２図は本発明の適用される光磁気記録装置を示す。
第３．４．５図は本発明を説明する記録磁界波形図を示
す。第６図は本発明の原理を示す回路図を示す、第７図
は第６図の部分の例である。FIG. 12 shows a magneto-optical recording device to which the present invention is applied. FIG. 3.4.5 shows a recording magnetic field waveform diagram illustrating the present invention. FIG. 6 shows a circuit diagram illustrating the principle of the present invention, and FIG. 7 is an example of the portion shown in FIG.
Claims (1)
温度上昇させ常温において信号に応じた残留磁界を生じ
させる記録装置において、該信号を時間的に変形して局
部的温度上昇を速かにするようにした光磁気記録装置。In a recording device that uses a magnetic medium with a Curie point and locally increases the temperature of the magnetic medium to generate a residual magnetic field according to a signal at room temperature, the signal is temporally transformed to quickly cause a local temperature rise. A magneto-optical recording device designed to
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13249483A JPS6025004A (en) | 1983-07-20 | 1983-07-20 | Opto-magnetic recording device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13249483A JPS6025004A (en) | 1983-07-20 | 1983-07-20 | Opto-magnetic recording device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6025004A true JPS6025004A (en) | 1985-02-07 |
Family
ID=15082681
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13249483A Pending JPS6025004A (en) | 1983-07-20 | 1983-07-20 | Opto-magnetic recording device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6025004A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0908423A1 (en) | 1997-10-09 | 1999-04-14 | Murata Manufacturing Co., Ltd. | Barium titanate semiconductive ceramic |
| CN1093104C (en) * | 1998-04-13 | 2002-10-23 | 株式会社村田制作所 | Semiconducting ceramic and semiconducting ceramic electronic element |
-
1983
- 1983-07-20 JP JP13249483A patent/JPS6025004A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0908423A1 (en) | 1997-10-09 | 1999-04-14 | Murata Manufacturing Co., Ltd. | Barium titanate semiconductive ceramic |
| CN1087719C (en) * | 1997-10-09 | 2002-07-17 | 株式会社村田制作所 | Barium titanate [-Base] semiconductive ceramic |
| CN1093104C (en) * | 1998-04-13 | 2002-10-23 | 株式会社村田制作所 | Semiconducting ceramic and semiconducting ceramic electronic element |
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