JPH02113402A - Modulation magnetic field generating device for magneto-optical recording and reproducing device - Google Patents

Modulation magnetic field generating device for magneto-optical recording and reproducing device

Info

Publication number
JPH02113402A
JPH02113402A JP26642288A JP26642288A JPH02113402A JP H02113402 A JPH02113402 A JP H02113402A JP 26642288 A JP26642288 A JP 26642288A JP 26642288 A JP26642288 A JP 26642288A JP H02113402 A JPH02113402 A JP H02113402A
Authority
JP
Japan
Prior art keywords
magnetic field
coil
magnetic
magneto
modulation
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
Application number
JP26642288A
Other languages
Japanese (ja)
Inventor
Takahiro Miyake
隆浩 三宅
Shigemi Maeda
茂己 前田
Tomoyuki Miyake
知之 三宅
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sharp Corp
Original Assignee
Sharp Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sharp Corp filed Critical Sharp Corp
Priority to JP26642288A priority Critical patent/JPH02113402A/en
Publication of JPH02113402A publication Critical patent/JPH02113402A/en
Pending legal-status Critical Current

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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
    • G11B11/10504—Recording
    • G11B11/10508—Recording by modulating only the magnetic field at the transducer

Landscapes

  • Recording Or Reproducing By Magnetic Means (AREA)

Abstract

PURPOSE:To reduce the magnetic field inverting time of the title device so that recording and erasure can be performed surely even when high-speed switching is made by adding a compensating voltage to a magnetic coil driving voltage when the polarity of a coil current is inverted. CONSTITUTION:A compensation circuit 7 is connected between a modulation circuit 5 which converts the recording data of a modulation magnetic field generating device into modulated pulses and an amplifier 6. The circuit 7 functions as a compensating voltage adding means, because the circuit 7 produces compensating pulses based on the modulated pulses and adds the compensating pulses to the rising edge of the modulated pulses. Accordingly, the driving voltage applied across a magnetic coil 1 becomes higher and the polarity of a coil current abruptly changes at the time of magnetic field inversion. Therefore, information can be recorded and erased surely even at the time of high-speed switching, because the inverting time can be reduced and no sufficient magnetic field is produced.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、磁界変調方式における光磁気記録再生装置の
変１１磁界発生回路に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic field generating circuit for a magneto-optical recording/reproducing device using a magnetic field modulation method.

［従来の技術〕 近年、磁界の極性を変化させることにより情報の記録お
よび消去を行う磁界変調方式が、新しい光記録方式とし
て注目されている。[Prior Art] In recent years, a magnetic field modulation method that records and erases information by changing the polarity of a magnetic field has been attracting attention as a new optical recording method.

磁界変調方式は、半導体レーザから出射されたレーザ光
を光磁気記録媒体に集光させ、その集光部の温度の上昇
に伴って保磁力を低下させることにより磁化方向を変化
しやすくしている。そこで、変調磁界発生装置の磁気コ
イルに、記録データに基づいて反転するコイル電流を供
給して変ＩＮ　％’ｔｌ界を発生させ、この変調磁界を
光磁気記録媒体に印加することにより、光磁気記録媒体
の磁化が反転し、情報の記録および消去が行われるよう
になっている。The magnetic field modulation method focuses laser light emitted from a semiconductor laser onto a magneto-optical recording medium, and makes it easier to change the direction of magnetization by lowering the coercive force as the temperature of the focusing area increases. . Therefore, by supplying a coil current that inverts based on recorded data to the magnetic coil of the modulated magnetic field generator to generate a variable IN%'tl field, and applying this modulated magnetic field to the magneto-optical recording medium, the magneto-optical The magnetization of the recording medium is reversed, and information is recorded and erased.

上記の磁界変調方式における変調磁界発生装置は、第５
図に示すように、磁気コイル１１および磁気コイル駆動
部１２によって構成されている。The modulated magnetic field generating device in the above magnetic field modulation method is the fifth
As shown in the figure, it is composed of a magnetic coil 11 and a magnetic coil drive section 12.

磁気コイル駆動部１２は、記録データを変調パルスに変
換する変調回路１３と、上記変調パルスを増幅する増幅
器１４と、磁気コイル１１に電流を流す負荷抵抗１５と
によって構成されており、増幅器１４と負荷抵抗１５の
間に磁気コイル１１が接続されている。The magnetic coil drive unit 12 includes a modulation circuit 13 that converts recorded data into modulation pulses, an amplifier 14 that amplifies the modulation pulses, and a load resistor 15 that allows current to flow through the magnetic coil 11. A magnetic coil 11 is connected between load resistors 15 .

記録データは、変調回路１３によってデータ変調パルス
に変換された後、増幅器１４によってコイル駆動電圧に
増幅され、磁気コイル１１と負荷抵抗１５に印加される
。このとき、磁気コイル１１と負荷抵抗１５は、ＬＲ直
列回路として機能するので、第６図（ａ）に示すように
、■。なるコイル駆動電圧が印加されると、磁気コイル
１１に流れる電流は、同図（ｂ）に示すような、１次遅
れ要素を有する過渡応答特性を示し定常のコイル電流Ｉ
０に達する。The recording data is converted into a data modulation pulse by the modulation circuit 13, and then amplified into a coil drive voltage by the amplifier 14, which is applied to the magnetic coil 11 and the load resistor 15. At this time, the magnetic coil 11 and the load resistor 15 function as an LR series circuit, so as shown in FIG. When a coil drive voltage of
reaches 0.

このため、例えば、第７図（ａ）に示すような変調パル
スが増幅器１４において増幅されてコイル駆動電圧とな
り、磁気コイル１１および負荷抵抗１５に印加されると
、磁気コイル１１には、同図（ｂ）に示すようなコイル
電流が流れ、磁界を反転させるようになっていた。For this reason, for example, when a modulated pulse as shown in FIG. A coil current as shown in (b) flows through the coil, reversing the magnetic field.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

ところが、上記従来の光磁気変調方式は、磁気コイル１
１において発生する変調磁界の強さが通常数百エルステ
ッド以上となるため、それに伴って磁気コイル１１のイ
ンダクタンスも数マイクロヘンリーと大きくなる。この
ような磁気コイル１１を用い、記録データの変調パルス
に従って記録磁界を反転させる場合、第７図（ｂ）に示
すように、磁気コイル駆動部１２から供給されるコイル
電流が、磁気コイル１１の大きいインダクタンスにより
変化が妨げられる。このため、定常値五〇または一１ｏ
に安定するまでに要するコイル電流反転時間Ｌ０が長く
なり、必要な磁界が得られるまでの磁界反転時間が長く
なってしまう。However, in the conventional magneto-optical modulation method, the magnetic coil 1
Since the strength of the modulated magnetic field generated in the magnetic coil 1 is usually several hundred oersted or more, the inductance of the magnetic coil 11 also increases accordingly, to several microhenries. When using such a magnetic coil 11 and reversing the recording magnetic field according to the modulation pulse of the recording data, the coil current supplied from the magnetic coil drive section 12 is Large inductances prevent changes. Therefore, the steady value is 50 or -1o.
The coil current reversal time L0 required for stabilization becomes longer, and the magnetic field reversal time required until the required magnetic field is obtained becomes longer.

従って、磁界を高速スイッチングにより反転させる場合
には、磁界の反転が完了しないうちに次の磁界を反転さ
せることとなり、図示しない光磁気記録媒体と磁気コイ
ル１１との距離を十分接近させなければ、記録および消
去に必要な磁界が不足し、オーバーライドが不安定にな
るという問題点を招来していた。Therefore, when the magnetic field is reversed by high-speed switching, the next magnetic field must be reversed before the reversal of the magnetic field is completed. The magnetic field necessary for recording and erasing is insufficient, leading to the problem that override becomes unstable.

〔課題を解決するための手段］ 本発明に係る光磁気記録再生装置の変調磁界発生装置は
、上記の課題を解決するために、記録情報に基づいて極
性が反転するコイル電流を磁気コイルに供給することに
より、記録時に光磁気記録媒体に印加する変調磁界を発
生する磁気記録再生装置の変調磁界発生装置において、
上記コイル電流の極性が反転する際に、コイル電流を発
生させる磁気コイル駆動電圧に補償電圧を付加する補償
電圧付加手段を備えたことを特徴としている。[Means for Solving the Problems] In order to solve the above problems, a modulated magnetic field generating device for a magneto-optical recording and reproducing device according to the present invention supplies a magnetic coil with a coil current whose polarity is reversed based on recorded information. In a modulated magnetic field generating device of a magnetic recording and reproducing device that generates a modulated magnetic field to be applied to a magneto-optical recording medium during recording,
The present invention is characterized by comprising compensation voltage adding means for adding a compensation voltage to the magnetic coil drive voltage that generates the coil current when the polarity of the coil current is reversed.

〔作　用〕[For production]

上記の構成により、変調磁界発生装置は、磁気コイルに
コイル電流を供給することにより、記録データに基づい
て極性が反転する変調磁界を発生させて、光磁気記録媒
体に記録および消去を行う。With the above configuration, the modulated magnetic field generating device supplies a coil current to the magnetic coil to generate a modulated magnetic field whose polarity is reversed based on recorded data, thereby recording and erasing information on a magneto-optical recording medium.

そこで、補償電圧付加手段は、磁界を反転させる際に、
コイル駆動電圧に補償電圧を付加して、磁気コイルに印
加する磁気コイル駆動電圧を大きくする。磁気コイル駆
動電圧が大きくなったことにより、コイル電流の極性の
変化が急速になる。Therefore, when reversing the magnetic field, the compensation voltage adding means
A compensation voltage is added to the coil drive voltage to increase the magnetic coil drive voltage applied to the magnetic coil. As the magnetic coil drive voltage increases, the polarity of the coil current changes rapidly.

従って、コイル電流の極性が反転するのに要する時間を
短縮させて、磁界反転時間を短縮することができる。そ
れゆえ、高速スイッチングによる磁界の反転においても
、磁界が不足することなく情報の記録および再生を確実
に行うことができ、これにより、安定したオーバーライ
ドを行うことができる。Therefore, the time required for the polarity of the coil current to reverse can be shortened, and the magnetic field reversal time can be shortened. Therefore, even when the magnetic field is reversed by high-speed switching, information can be reliably recorded and reproduced without running out of the magnetic field, and thereby stable override can be performed.

〔実施例１〕 本発明の一実施例を第１図ないし第３図に基づいて説明
すれば、以下の通りである。[Embodiment 1] An embodiment of the present invention will be described below based on FIGS. 1 to 3.

光磁気記録再生装置において、変調磁界発生装置は、第
１図に示すように、磁気コイル１および磁気コイル駆動
部２によって構成されており、光磁気記録媒体３の上方
に配置されている。また、光磁気記録媒体３の下方には
、光学手段４が配置され、光磁気記録媒体３にレーザ光
を照射するようになっている。In the magneto-optical recording and reproducing apparatus, the modulated magnetic field generating device is comprised of a magnetic coil 1 and a magnetic coil drive section 2, as shown in FIG. Further, an optical means 4 is arranged below the magneto-optical recording medium 3, and is configured to irradiate the magneto-optical recording medium 3 with a laser beam.

上記磁気コイル駆動部２は、第２図に示すように、記録
データを変調パルスに変換する変調回路５と、上記変調
パルスを増幅する増幅器６と、変調パルスに補償パルス
を付加する補償回路７と、磁気コイル１に電流を流す負
荷抵抗８とによって構成されており、増幅器６と負荷抵
抗８の間に磁気コイル１が接続されている。As shown in FIG. 2, the magnetic coil drive section 2 includes a modulation circuit 5 that converts recorded data into modulation pulses, an amplifier 6 that amplifies the modulation pulses, and a compensation circuit 7 that adds compensation pulses to the modulation pulses. and a load resistor 8 that allows current to flow through the magnetic coil 1. The magnetic coil 1 is connected between the amplifier 6 and the load resistor 8.

上記補償回路７は、変調回路５と増幅器６の間に並列接
続されており、変調回路５からの変調パルスが反転する
際に、この変調パルスに基づいて補償パルスを生成し、
変調パルスの立ち上がりエツジに付加するようになって
いる。上記補償パルスは、変調パルスとともに増幅器６
により増幅されて、通常のコイル駆動電圧に対する補償
電圧となることから、補償回路７は、補償電圧付加手段
として機能するようになっている。The compensation circuit 7 is connected in parallel between the modulation circuit 5 and the amplifier 6, and generates a compensation pulse based on the modulation pulse when the modulation pulse from the modulation circuit 5 is inverted,
It is added to the rising edge of the modulation pulse. The compensation pulse is sent to the amplifier 6 along with the modulation pulse.
The compensation circuit 7 functions as a compensation voltage adding means because the compensation voltage is amplified by the voltage and becomes a compensation voltage for the normal coil drive voltage.

上記の構成において、光磁気記録媒体３は、光学手段４
によりレーザ光が照射されて、局部的に温度が上昇し保
磁力が低下することにより、磁化方向が反転しやすい状
態になる。In the above configuration, the magneto-optical recording medium 3 includes the optical means 4
When the laser beam is irradiated, the temperature locally increases and the coercive force decreases, resulting in a state in which the magnetization direction is likely to be reversed.

一方、記録データは、変調回路５によって変調パルスに
変換された後、極性が反転する際に補償回路７によって
補償パルスが付加される。そして、増幅器６において、
磁気コイル１を駆動するコイル駆動電圧まで増幅されて
磁気コイル１と負荷抵抗日からなる直列回路に印加され
る。すると、磁気コイルｌにコイル電流が流れ磁気コイ
ル１に変調磁界が発生する。磁気記録媒体３は、この変
調磁界が印加されることにより、磁化が反転されて情報
の記録および消去が行われる。On the other hand, the recording data is converted into a modulation pulse by the modulation circuit 5, and then a compensation pulse is added by the compensation circuit 7 when the polarity is reversed. Then, in the amplifier 6,
The voltage is amplified to a coil drive voltage that drives the magnetic coil 1 and is applied to a series circuit consisting of the magnetic coil 1 and a load resistor. Then, a coil current flows through the magnetic coil 1, and a modulated magnetic field is generated in the magnetic coil 1. When this modulated magnetic field is applied to the magnetic recording medium 3, the magnetization is reversed and information is recorded and erased.

ここで、例えば、第３図（ａ）に示すように、記録デー
タに応じて極性が反転する変調パルスに対して、補償回
路７は、同図（ｂ）に示すような補償パルスを生成して
、上記変調パルスに付加する。そして、同図（Ｃ）に示
すように、補償パルスが付加された変調パルスが増幅器
６において増幅され、磁気コイルｌおよび負荷抵抗８に
印加されると、磁気コイル１には、同図（ｄ）に示すよ
うなコイル電流が流れる。このコイル電流は、補償電圧
の増加分に応じた過渡応答特性で極性を反転しようとす
るため、補償電圧骨が増加したコイル駆動電圧に応じた
コイル電流の定常値に達するまでに通常のコイル電流の
定常値１０または−１０に達する。従って、コイル電流
は、変調パルスに補償パルスを付加しない場合と比較し
て、極性が反転するのに要するコイル電流反転時間Ｌ０
が短くなっている。Here, for example, as shown in FIG. 3(a), the compensation circuit 7 generates a compensation pulse as shown in FIG. and is added to the above modulated pulse. As shown in (C) of the same figure, when the modulated pulse to which the compensation pulse has been added is amplified by the amplifier 6 and applied to the magnetic coil l and the load resistor 8, the magnetic coil 1 is ) flows in the coil. This coil current tries to reverse its polarity with a transient response characteristic according to the increase in the compensation voltage. reaches a steady-state value of 10 or -10. Therefore, the coil current reversal time L0 required for the polarity to be reversed is longer than when no compensation pulse is added to the modulation pulse.
is shorter.

また、補償回路７において生成される補償電圧は、同図
（ｂ）に示すように方形となっているが、補償回路７を
微分回路にて構成し、同図（ｅ）に示すように、変調パ
ルスに対して微分された補償パルスを生成してもよい。Furthermore, the compensation voltage generated in the compensation circuit 7 is square as shown in FIG. A compensation pulse may be generated that is differentiated with respect to the modulation pulse.

このようにして生成された補償パルスを変調パルスに付
加すると、同図（ｆ）に示すようになり、この変調パル
スが増幅されたコイル駆動電圧を磁気コイル１および負
荷抵抗８に印加すると、磁気コイル１には、同図（ｄ）
に示すようなコイル電流が流れる。When the compensation pulse generated in this way is added to the modulation pulse, it becomes as shown in FIG. Coil 1 has the same figure (d).
A coil current flows as shown in the figure.

従って、補償回路７において生成される補償パルスの波
形は、方形に限定されずコイル駆動電圧を補償し、磁気
コイル１に同図（ｄ）に示すようなコイル電流を流すこ
とができれば、形状は問わない。Therefore, the waveform of the compensation pulse generated in the compensation circuit 7 is not limited to a rectangular shape, but if the coil drive voltage can be compensated and a coil current as shown in FIG. No question.

〔実施例２〕 本発明の他の実施例を第４図に基づいて説明すれば、以
下の通りである。[Embodiment 2] Another embodiment of the present invention will be described below based on FIG.

なお、実施例１と同様の機能を有する部材には、同一の
符号を付記してその説明を省略する。Note that members having the same functions as those in the first embodiment are denoted by the same reference numerals, and the explanation thereof will be omitted.

変調磁界発生装置は、第４図に示すように、変調回路５
と、増幅器６と、負荷抵抗８によって構成されており、
増幅器６と負荷抵抗８の間に接続された磁気コイルｌを
駆動するようになっている。The modulated magnetic field generator includes a modulating circuit 5 as shown in FIG.
, an amplifier 6, and a load resistor 8,
A magnetic coil l connected between an amplifier 6 and a load resistor 8 is driven.

また、磁気コイル１のモニター電圧が帰還されて変調パ
ルス電圧と作動増幅されるように、磁気コイル１と負荷
抵抗８の間と、変調回路５と増幅器６の間とが接続され
て定電流回路が構成されている。In addition, the constant current circuit is connected between the magnetic coil 1 and the load resistor 8 and between the modulation circuit 5 and the amplifier 6 so that the monitor voltage of the magnetic coil 1 is fed back and is operationally amplified with the modulated pulse voltage. is configured.

上記の構成によれば、磁気コイル１のモニター電圧と変
調パルス電圧を作動増幅することにより、コイル電流の
極性が反転する際にコイル駆動電圧が補償されてコイル
電流の極性の反転が速くなる。According to the above configuration, by operationally amplifying the monitor voltage and modulated pulse voltage of the magnetic coil 1, the coil drive voltage is compensated when the polarity of the coil current is reversed, and the polarity of the coil current is quickly reversed.

また、本実施例においては、磁気コイルｌの電圧を変調
パルスに帰還させることによりコイル駆動電圧の補償を
行うので、実施例１における第２図に示した補償回路７
を必要とせず、回路構成を簡単にすることができる。Further, in this embodiment, since the coil drive voltage is compensated by feeding back the voltage of the magnetic coil l to the modulation pulse, the compensation circuit 7 shown in FIG. 2 in the first embodiment
, and the circuit configuration can be simplified.

〔発明の効果〕〔Effect of the invention〕

本発明の光磁気記録再生装置の変調磁界発生装置は、以
上のように、記録情報に基づいて極性が反転するコイル
電流を磁気コイルに供給することにより、記録時に光磁
気記録媒体に印加する変調磁界を発生する磁気記録再生
装置の変調磁界発生装置において、上記コイル電流の極
性が反転する際に、コイル電流を発生させる磁気コイル
駆動電圧に補償電圧を付加する補償電圧付加手段を備え
た構成である。As described above, the modulated magnetic field generating device of the magneto-optical recording and reproducing apparatus of the present invention applies modulation to the magneto-optical recording medium during recording by supplying the magnetic coil with a coil current whose polarity is reversed based on recorded information. A modulated magnetic field generating device for a magnetic recording and reproducing device that generates a magnetic field is configured to include compensation voltage adding means for adding a compensation voltage to a magnetic coil drive voltage that generates a coil current when the polarity of the coil current is reversed. be.

これにより、補償電圧付加手段は、磁界を反転させる際
に、所定のコイル駆動電圧に補償電圧を付加して、磁気
コイルに印加する磁気コイル駆動電圧を大きくする。コ
イル電流は、このコイル駆動電圧に応じて変化が急にな
り、コイル電流の極性が反転するのに要する時間が短く
なる。Thereby, the compensation voltage adding means increases the magnetic coil drive voltage applied to the magnetic coil by adding the compensation voltage to the predetermined coil drive voltage when reversing the magnetic field. The coil current changes rapidly in accordance with this coil drive voltage, and the time required for the polarity of the coil current to reverse becomes shorter.

従って、磁界反転時間を短縮することができ、高速スイ
ッチングによる磁界の反転においても、磁界が不足する
ことなく確実に情報の記録および消去を行うことができ
、安定したオーバーライドを行うことができるという効
果を奏する。Therefore, the magnetic field reversal time can be shortened, and even when the magnetic field is reversed due to high-speed switching, information can be reliably recorded and erased without running out of magnetic field, and stable override can be performed. play.

【図面の簡単な説明】[Brief explanation of drawings]

第１図ないし第３図は本発明の一実施例を示すものであ
って、第１図は光磁気記録再生装置における磁気発生装
置の配置を示す説明図、第２図は変調磁界発生装置を示
すブロック図、第３図（ａ）は変調パルスの時間変化を
示すグラフ、同図（ｂ）は補償パルスの時間変化を示す
グラフ、同図（Ｃ）は補償パルスが付加された変調パル
スの時間変化を示すグラフ、同図（ｄ）はコイル電流の
時間変化を示すグラフ、同図（ｅ）は微分された補償パ
ルスの時間変化を示すグラフ、同図（ｆ）は微分された
補償パルスが付加された変調パルスの時間変化を示すグ
ラフ、第４図は本発明の他の実施例を示すものであって
、変調磁界発生装置を示すブロック図である。 第５図ないし第７図は従来例を示すものであって、第５
図は変調磁界発生装置を示すブロック図、第６図（ａ）
は磁気コイルおよび負荷抵抗がら第 図 第 図1 to 3 show an embodiment of the present invention, in which FIG. 1 is an explanatory diagram showing the arrangement of a magnetic field generating device in a magneto-optical recording/reproducing device, and FIG. Figure 3(a) is a graph showing the time change of the modulated pulse, Figure 3(b) is a graph showing the time change of the compensation pulse, and Figure 3(C) is the graph of the modulated pulse to which the compensation pulse has been added. Graph showing the time change, (d) is a graph showing the time change of the coil current, (e) is a graph showing the time change of the differentiated compensation pulse, (f) is the differentiated compensation pulse FIG. 4 is a graph showing a temporal change in a modulated pulse to which is added, and is a block diagram showing a modulated magnetic field generating device, which shows another embodiment of the present invention. 5 to 7 show conventional examples.
The figure is a block diagram showing the modulated magnetic field generator, Fig. 6(a)
The diagram shows the magnetic coil and load resistance.

Claims (1)

【特許請求の範囲】[Claims] １、記録情報に基づいて極性が反転するコイル電流を磁
気コイルに供給することにより、記録時に光磁気記録媒
体に印加する変調磁界を発生する磁気記録再生装置の変
調磁界発生装置において、上記コイル電流の極性が反転
する際に、コイル電流を発生させる磁気コイル駆動電圧
に補償電圧を付加する補償電圧付加手段を備えたことを
特徴とする光磁気記録再生装置の変調磁界発生回路。1. In a modulated magnetic field generating device of a magnetic recording and reproducing device that generates a modulated magnetic field to be applied to a magneto-optical recording medium during recording by supplying a coil current whose polarity is reversed based on recorded information to a magnetic coil, the coil current 1. A modulated magnetic field generating circuit for a magneto-optical recording/reproducing device, comprising compensation voltage adding means for adding a compensation voltage to a magnetic coil drive voltage that generates a coil current when the polarity of the magneto-optical recording/reproducing device is reversed.
JP26642288A 1988-10-21 1988-10-21 Modulation magnetic field generating device for magneto-optical recording and reproducing device Pending JPH02113402A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP26642288A JPH02113402A (en) 1988-10-21 1988-10-21 Modulation magnetic field generating device for magneto-optical recording and reproducing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP26642288A JPH02113402A (en) 1988-10-21 1988-10-21 Modulation magnetic field generating device for magneto-optical recording and reproducing device

Publications (1)

Publication Number Publication Date
JPH02113402A true JPH02113402A (en) 1990-04-25

Family

ID=17430715

Family Applications (1)

Application Number Title Priority Date Filing Date
JP26642288A Pending JPH02113402A (en) 1988-10-21 1988-10-21 Modulation magnetic field generating device for magneto-optical recording and reproducing device

Country Status (1)

Country Link
JP (1) JPH02113402A (en)

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