JP2505837Y2 - Information recording device - Google Patents
Information recording deviceInfo
- Publication number
- JP2505837Y2 JP2505837Y2 JP1237891U JP1237891U JP2505837Y2 JP 2505837 Y2 JP2505837 Y2 JP 2505837Y2 JP 1237891 U JP1237891 U JP 1237891U JP 1237891 U JP1237891 U JP 1237891U JP 2505837 Y2 JP2505837 Y2 JP 2505837Y2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- magneto
- optical disk
- magnetic
- distance
- 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
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- Recording Or Reproducing By Magnetic Means (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本考案は、情報記録媒体としての
光磁気ディスクに磁界を印加するとともに、レーザー光
等の光ビームを照射して情報の記録を行う情報記録装置
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording apparatus for recording information by applying a magnetic field to a magneto-optical disk as an information recording medium and irradiating a light beam such as a laser beam.
【０００２】[0002]
【従来の技術】従来からレーザー光等の光ビームを用い
た光学式の記録及び／または再生装置には、記録媒体と
して光ディスクが用いられている。光ディスクには、機
能別に再生専用のもの、ユーザーによる記録が一回だけ
できる追記型のもの、記録・消去の繰り返しが可能な書
換え型のものがある。2. Description of the Related Art Conventionally, an optical disc is used as a recording medium in an optical recording and / or reproducing apparatus using a light beam such as a laser beam. There are two types of optical discs, one is a read-only type for each function, a write-once type that allows the user to record only once, and a rewritable type that allows repeated recording and erasing.
【０００３】書換えを実現させる方式の一つに、光磁気
ディスクを用い、レーザー光と磁界による記録消去を行
う熱磁気記録方式がある（例えば、「応用物理」第５７
巻第８号（1988）第1151頁乃至第1161頁参照）。One of the methods for realizing rewriting is a thermomagnetic recording method in which a magneto-optical disk is used to perform recording and erasing with a laser beam and a magnetic field (for example, "Applied Physics", No. 57).
Vol. 8 (1988) pp. 1151 to 1161).
【０００４】これは、レーザー光を熱源として用い、光
ディスクの磁性膜にレーザー光を照射して局部的に昇温
し、キュリー点温度以上になると磁性膜の保持力が減少
するので、その状態で電磁コイル等の外部磁界印加手段
で磁界を印加すると、その磁界に沿って磁性膜が磁化さ
れることを利用したものである。This is because the laser beam is used as a heat source to irradiate the magnetic film of the optical disk with the laser beam to locally raise the temperature, and when the temperature exceeds the Curie point, the coercive force of the magnetic film decreases. This is because when a magnetic field is applied by an external magnetic field applying means such as an electromagnetic coil, the magnetic film is magnetized along the magnetic field.
【０００５】ここで、磁性膜に一定の磁界が印加される
様に光磁気ディスクと磁界印加手段とは接触することな
くできるだけ接近させ、かつ一定の距離を保たなければ
ならない。その光磁気ディスクと磁界印加手段との距離
を一定に保つのに、磁界発生手段としての永久磁石と、
検出手段としての磁気検出素子を用いるものがあり、図
２にその概略構成図を示す。Here, the magneto-optical disk and the magnetic field applying means must be brought as close as possible to each other and a constant distance must be maintained so that a constant magnetic field is applied to the magnetic film. In order to keep the distance between the magneto-optical disk and the magnetic field applying means constant, a permanent magnet as magnetic field generating means,
There is one using a magnetic detection element as a detection means, and a schematic configuration diagram thereof is shown in FIG.
【０００６】１は記録媒体としての光磁気ディスクであ
る。１０は光ビーム照射手段としての光ヘッドで、光磁
気ディスク１の磁性膜上（光ビーム照射点３）に、図示
しないレーザー源から発振されたレーザー光の焦光を合
わすための対物レンズ２を備える。この対物レンズ２は
ホルダー９に保持され、ホルダー９の周囲に対物レンズ
２をフォーカス方向（上下方向）に動かすボイスコイル
４が巻回されている。Reference numeral 1 is a magneto-optical disk as a recording medium. Reference numeral 10 denotes an optical head as a light beam irradiating means, which has an objective lens 2 on the magnetic film of the magneto-optical disk 1 (light beam irradiating point 3) for focusing a laser beam oscillated from a laser source (not shown). Prepare The objective lens 2 is held by a holder 9, and a voice coil 4 for moving the objective lens 2 in the focus direction (vertical direction) is wound around the holder 9.
【０００７】５は光磁気ディスク１の磁性膜に、情報を
記録するための磁界を印加する外部磁界印加手段として
の磁気ヘッドで、ベース８上に設けられる。A magnetic head 5 is provided on the base 8 as an external magnetic field applying means for applying a magnetic field for recording information to the magnetic film of the magneto-optical disk 1.
【０００８】６は光磁気ディスク１と磁気ヘッド５の距
離を測定するための磁界を発生する永久磁石、７は永久
磁石６の発生する磁界の強度を検出する磁気検出素子と
してのホール素子である。永久磁石６は対物レンズ２の
ホルダー９上に、ホール素子７は磁気ヘッド５が設けら
れるベース８上に、光磁気ディスク１を介して永久磁石
６とホール素子７が対称になる位置に各々設けられてい
る。Reference numeral 6 is a permanent magnet for generating a magnetic field for measuring the distance between the magneto-optical disk 1 and the magnetic head 5, and 7 is a Hall element as a magnetic detecting element for detecting the strength of the magnetic field generated by the permanent magnet 6. . The permanent magnet 6 is provided on the holder 9 of the objective lens 2, the Hall element 7 is provided on the base 8 on which the magnetic head 5 is provided, and at positions where the permanent magnet 6 and the Hall element 7 are symmetrical with each other through the magneto-optical disk 1. Has been.
【０００９】以上のように構成された情報記録装置に於
て、磁気ヘッド５と光磁気ディスク１の距離を一定に保
つことは、対物レンズ２と光磁気ディスク１の距離が、
光ヘッド１０のフォーカス制御により一定に保たれるこ
とを利用して行われる。つまり、対物レンズ２と光磁気
ディスク１の距離が一定に保たれるので、磁気ヘッド５
と対物レンズ２の距離を一定に保つことで、磁気ヘッド
５と光磁気ディスク１の距離も一定に保たれる。In the information recording apparatus configured as described above, keeping the distance between the magnetic head 5 and the magneto-optical disk 1 constant means that the distance between the objective lens 2 and the magneto-optical disk 1 is
This is performed by using the fact that the focus is controlled by the focus control of the optical head 10. That is, since the distance between the objective lens 2 and the magneto-optical disk 1 is kept constant, the magnetic head 5
By keeping the distance between the objective lens 2 and the objective lens 2 constant, the distance between the magnetic head 5 and the magneto-optical disk 1 is also kept constant.
【００１０】ここで、磁気ヘッド５と対物レンズ２の距
離制御は、永久磁石６の発生する磁界の強度をホール素
子７で検出し、その検出される強度を一定に保つよう
に、磁気ヘッド５を設けたベース８を上下方向に移動さ
せることで行う。Here, in controlling the distance between the magnetic head 5 and the objective lens 2, the magnetic field intensity of the magnetic field generated by the permanent magnet 6 is detected by the Hall element 7, and the detected magnetic field intensity is kept constant. It is performed by moving the base 8 provided with the up and down direction.
【００１１】[0011]
【考案が解決しようとする課題】しかしながら、永久磁
石６が発生する磁界は、光磁気ディスク１上の光ビーム
照射点３で光磁気ディスク１に対してディスク面と交差
する方向の磁界を発生する。即ち、磁気ヘッド５が情報
記録のために光磁気ディスク１に印加する磁界は、光ビ
ーム照射点３において永久磁石６が発生する磁界分だけ
バイアスを持つことになる。従って、磁気ヘッド５によ
り光磁気ディスク１に印加される磁界が適正な強度とな
らず、正確な情報記録ができないという問題があった。However, the magnetic field generated by the permanent magnet 6 generates a magnetic field in the direction intersecting the disk surface with respect to the magneto-optical disk 1 at the light beam irradiation point 3 on the magneto-optical disk 1. . That is, the magnetic field applied to the magneto-optical disk 1 by the magnetic head 5 for recording information has a bias corresponding to the magnetic field generated by the permanent magnet 6 at the light beam irradiation point 3. Therefore, the magnetic field applied to the magneto-optical disk 1 by the magnetic head 5 does not have an appropriate intensity, and there is a problem that accurate information recording cannot be performed.
【００１２】本考案は、斯様な点に鑑みて為されたもの
で、良好で確実な情報記録が可能な情報記録装置を提供
するものである。The present invention has been made in view of such a point, and provides an information recording apparatus capable of recording good and reliable information.
【００１３】[0013]
【課題を解決するための手段】本考案は、情報記録のた
めに記録媒体に光ビームを照射する光ビーム照射手段
と、情報記録のために記録媒体に磁界を印加する磁界印
加手段と、光ビーム照射手段と磁界印加手段との距離を
検出するための磁界発生手段及び該磁界発生手段で発生
される磁界を検出する検出手段とを備え、検出手段で検
出される磁界強度が一定に保持されるよう前記磁界印加
手段が移動制御される情報記録装置であって、前記磁界
発生手段において互いに逆向きの磁界を発生する少なく
とも２つの磁界発生素子を備えるものである。The present invention is directed to a light beam irradiating means for irradiating a recording medium with a light beam for recording information, a magnetic field applying means for applying a magnetic field to the recording medium for recording information, and A magnetic field generating means for detecting a distance between the beam irradiating means and the magnetic field applying means and a detecting means for detecting a magnetic field generated by the magnetic field generating means are provided, and the magnetic field strength detected by the detecting means is kept constant. Thus, the information recording apparatus is such that the magnetic field applying means is controlled to move, and is provided with at least two magnetic field generating elements that generate mutually opposite magnetic fields in the magnetic field generating means.
【００１４】[0014]
【作用】互いに逆向きの磁界を発生する少なくとも２つ
の磁界発生素子により、記録媒体の光ビーム照射点にお
ける磁界発生素子が発生する磁界は相殺される。The magnetic field generated by the magnetic field generating element at the light beam irradiation point of the recording medium is canceled by the at least two magnetic field generating elements which generate magnetic fields in opposite directions.
【００１５】[0015]
【実施例】本考案の情報記録装置の一実施例について、
図１、図２を参照しながら説明を行う。[Example] An example of the information recording apparatus of the present invention,
Description will be given with reference to FIGS. 1 and 2.
【００１６】図１は、本考案情報記録装置の一実施例の
概略構成図である。尚、図２と同一部分には、同じ符号
を付して説明を省略する。FIG. 1 is a schematic block diagram of an embodiment of the information recording apparatus of the present invention. The same parts as those in FIG. 2 are designated by the same reference numerals and the description thereof will be omitted.
【００１７】図１に於て、１１は永久磁石６が発生する
磁界と、逆方向の磁界を発生する永久磁石である。永久
磁石１１は光磁気ディスク１の光ビーム照射点３に於
て、距離測定のための永久磁石６が発生する磁界を相殺
するように、対物レンズ２を中心にした永久磁石６と対
称な位置の対物レンズ２のホルダー９上に設けてある。In FIG. 1, reference numeral 11 is a permanent magnet that generates a magnetic field in the opposite direction to the magnetic field generated by the permanent magnet 6. At the light beam irradiation point 3 of the magneto-optical disk 1, the permanent magnet 11 is symmetrical to the permanent magnet 6 centered on the objective lens 2 so as to cancel the magnetic field generated by the permanent magnet 6 for distance measurement. It is provided on the holder 9 of the objective lens 2.
【００１８】１２は磁気検出素子としてのホール素子で
ある。このホール素子１２は、光磁気ディスク１を介し
て永久磁石１１と対称な位置の磁気ヘッドのベース８上
に設けられ、永久磁石１１の発生する距離測定用磁界の
強度検出を行う。Reference numeral 12 is a Hall element as a magnetic detection element. The Hall element 12 is provided on the base 8 of the magnetic head at a position symmetrical to the permanent magnet 11 via the magneto-optical disk 1 and detects the strength of the distance measuring magnetic field generated by the permanent magnet 11.
【００１９】斯様な装置に於て、光磁気ディスク１に情
報の書き込みを行う場合について説明する。The case of writing information on the magneto-optical disk 1 in such a device will be described.
【００２０】光磁気ディスク１への情報の書き込みは、
レーザー源で発振されたレーザー光が、光ヘッド１０の
対物レンズ２により光磁気ディスク１上の光ビーム照射
点３に焦光され、光ビーム照射点３が昇温しキュリー点
温度以上の磁性膜磁界保持力が減少した時に、磁気ヘッ
ド５により記録情報に応じた磁界を印加することで行わ
れる。Writing information to the magneto-optical disk 1
The laser light oscillated by the laser source is focused on the light beam irradiation point 3 on the magneto-optical disk 1 by the objective lens 2 of the optical head 10, the temperature of the light beam irradiation point 3 rises, and the magnetic film has a Curie point temperature or higher. When the magnetic field holding force decreases, the magnetic head 5 applies a magnetic field according to the recorded information.
【００２１】この光磁気ディスク１への情報の書き込み
時には、対物レンズ２と光磁気ディスク１、磁気ヘッド
５と光磁気ディスク１の間の距離が一定になるように制
御される。即ち、光磁気ディスク１上の光ビーム照射点
３に前述のレーザー光を正確に焦光させるためであり、
また磁気ヘッド５が磁性膜に常に一定の磁界を印加でき
るように、磁気ヘッド５が光磁気ディスク１に接触する
ことなくできるだけ接近させ、かつ一定の距離を保持さ
せるためである。At the time of writing information on the magneto-optical disk 1, the distance between the objective lens 2 and the magneto-optical disk 1 and between the magnetic head 5 and the magneto-optical disk 1 is controlled to be constant. That is, in order to accurately focus the above-mentioned laser light on the light beam irradiation point 3 on the magneto-optical disk 1,
This is also because the magnetic head 5 should be as close as possible to the magneto-optical disk 1 without contacting the magneto-optical disk 1 and a constant distance should be maintained so that the magnetic head 5 can always apply a constant magnetic field to the magnetic film.
【００２２】対物レンズ２と光磁気ディスク１の距離制
御は、レーザー源から発振されたレーザー光が、光ヘッ
ド１０の対物レンズ２で光ビーム照射点３に焦光するよ
うに行われる。このとき、距離制御のための対物レンズ
２の移動は、光ヘッド１０に備えられたボイスコイル４
により行う。The distance between the objective lens 2 and the magneto-optical disk 1 is controlled so that the laser light emitted from the laser source is focused on the light beam irradiation point 3 by the objective lens 2 of the optical head 10. At this time, the movement of the objective lens 2 for the distance control is performed by the voice coil 4 provided in the optical head 10.
By.
【００２３】また、このフォーカス制御を利用して、磁
気ヘッド５と光磁気ディスク１の距離制御が行われる。
つまり、フォーカス制御により、対物レンズ２と光磁気
ディスク１の距離が一定に保たれるので、磁気ヘッド５
と対物レンズ２の距離を一定に保つことで、磁気ヘッド
５と光磁気ディスク１の距離も一定に保たれる。この磁
気ヘッド５と対物レンズ２の距離制御は、距離測定用の
永久磁石６及び１１が発生する夫々の磁界の強度を、ホ
ール素子７及び１２が夫々検出し、その強度を常に一定
に検出するように磁気ヘッド５のベース８を上下方向に
移動させて行われる。即ち、ホール素子７及び１２が永
久磁石６及び１１の磁界を常に一定に検出するように磁
気ヘッド５を移動制御することで、ホール素子７及び１
２と同一ベース８上にある磁気ヘッド５と、永久磁石６
及び１１と同一ホルダー上にある対物レンズ２との距離
が一定に保たれる。この永久磁石とホール素子を二組備
えた距離測定では、従来例である図２に示される永久磁
石６とホール素子７一組による距離測定に較べ、異なる
２点での距離測定が可能となり、光磁気ディスク１の変
動に対し、距離制御精度の向上を図ることができる。同
様に、永久磁石及びホール素子をより追加して設けるこ
とで、より一層の距離制御精度向上が図れる。Further, the distance between the magnetic head 5 and the magneto-optical disk 1 is controlled by utilizing this focus control.
That is, since the distance between the objective lens 2 and the magneto-optical disk 1 is kept constant by the focus control, the magnetic head 5
By keeping the distance between the objective lens 2 and the objective lens 2 constant, the distance between the magnetic head 5 and the magneto-optical disk 1 is also kept constant. In controlling the distance between the magnetic head 5 and the objective lens 2, the Hall elements 7 and 12 detect the strengths of the magnetic fields generated by the permanent magnets 6 and 11 for distance measurement, and the strengths are constantly detected. As described above, the base 8 of the magnetic head 5 is moved in the vertical direction. That is, the Hall elements 7 and 12 are moved and controlled so that the magnetic fields of the permanent magnets 6 and 11 are constantly detected.
2 and a magnetic head 5 on the same base 8 and a permanent magnet 6
The distance between the objective lens 2 and 11 and the objective lens 2 on the same holder is kept constant. In the distance measurement provided with two sets of the permanent magnet and the hall element, it is possible to measure the distance at two different points, as compared with the distance measurement with one set of the permanent magnet 6 and the hall element 7 shown in FIG. 2 which is a conventional example. It is possible to improve the accuracy of distance control with respect to the fluctuation of the magneto-optical disk 1. Similarly, by further providing a permanent magnet and a Hall element, the distance control accuracy can be further improved.
【００２４】さて、本実施例では、永久磁石６が発生す
る光ビーム照射点３での光磁気ディスク１のディスク面
に交差する方向の磁界に対し、永久磁石６と対物レンズ
２を中心とする対称位置に永久磁石６と逆方向の磁界を
発生する永久磁石１１を設けているので、光ビーム照射
点３のディスク面交差方向の磁界成分が相殺され、距離
測定用の永久磁石による影響が排除される。而して、磁
気ヘッド５により情報記録のために光磁気ディスク１に
印加される磁界は、永久磁石６及び１１による距離測定
用の永久磁石の影響を受けることはなく、良好で正確な
情報記録が行われる。Now, in this embodiment, the permanent magnet 6 and the objective lens 2 are centered with respect to the magnetic field generated by the permanent magnet 6 in the direction intersecting the disk surface of the magneto-optical disk 1 at the light beam irradiation point 3. Since the permanent magnet 11 that generates a magnetic field in the opposite direction to the permanent magnet 6 is provided at the symmetrical position, the magnetic field component of the light beam irradiation point 3 in the disk surface intersecting direction is canceled, and the influence of the permanent magnet for distance measurement is eliminated. To be done. Thus, the magnetic field applied to the magneto-optical disk 1 by the magnetic head 5 for recording information is not affected by the permanent magnets 6 and 11 for measuring the distance, and good and accurate information recording is possible. Is done.
【００２５】[0025]
【考案の効果】本考案は、以上の説明から明かな如く、
距離測定用の永久磁石が発生する磁界と逆方向の磁界を
発生する永久磁石を備え、光ビーム照射点での距離測定
用磁界が相殺される。従って、情報記録のために磁界印
加手段が印加する磁界への距離測定用磁石による影響を
排除できるため、良好で確実な情報記録を行うことがで
きる。[Effect of the Invention] As is apparent from the above description, the present invention is
A permanent magnet that generates a magnetic field in a direction opposite to the magnetic field generated by the permanent magnet for distance measurement is provided, and the magnetic field for distance measurement at the light beam irradiation point is canceled. Therefore, the influence of the distance measuring magnet on the magnetic field applied by the magnetic field applying means for information recording can be eliminated, and good and reliable information recording can be performed.
【図１】本考案情報記録装置の一実施例の概略構成図で
ある。FIG. 1 is a schematic configuration diagram of an embodiment of an information recording apparatus of the present invention.
【図２】従来情報記録装置の一実施例の概略構成図であ
る。FIG. 2 is a schematic configuration diagram of an embodiment of a conventional information recording device.
１ 光磁気ディスク（記録媒体） ２ 対物レンズ ３ 光ビーム照射点 ４ ボイスコイル ５ 磁気ヘッド ６ 永久磁石 ７ 磁気検出素子（ホール素子） ８ ベース ９ ホルダー １０ 光ヘッド １１ 永久磁石 １２ 磁気検出素子（ホール素子） 1 Magneto-optical disk (recording medium) 2 Objective lens 3 Light beam irradiation point 4 Voice coil 5 Magnetic head 6 Permanent magnet 7 Magnetic detection element (Hall element) 8 Base 9 Holder 10 Optical head 11 Permanent magnet 12 Magnetic detection element (Hall element) )
Claims (1)
射する光ビーム照射手段と、情報記録のために記録媒体
に磁界を印加する磁界印加手段と、光ビーム照射手段と
磁界印加手段との距離を検出するための磁界発生手段及
び該磁界発生手段で発生される磁界を検出する検出手段
とを備え、検出手段で検出される磁界強度が一定に保持
されるよう前記磁界印加手段が移動制御される情報記録
装置において、前記磁界発生手段は互いに逆向きの磁界
を発生する少なくとも２つの磁界発生素子からなること
を特徴とする情報記録装置。1. A light beam irradiation means for irradiating a recording medium with a light beam for recording information, a magnetic field applying means for applying a magnetic field to the recording medium for recording information, a light beam irradiation means and a magnetic field applying means. A magnetic field generating means for detecting the distance of the magnetic field and a detecting means for detecting the magnetic field generated by the magnetic field generating means, and the magnetic field applying means is moved so that the magnetic field strength detected by the detecting means is kept constant. In the controlled information recording apparatus, the magnetic field generating means comprises at least two magnetic field generating elements which generate magnetic fields in mutually opposite directions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1237891U JP2505837Y2 (en) | 1991-03-07 | 1991-03-07 | Information recording device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1237891U JP2505837Y2 (en) | 1991-03-07 | 1991-03-07 | Information recording device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04111016U JPH04111016U (en) | 1992-09-28 |
| JP2505837Y2 true JP2505837Y2 (en) | 1996-08-07 |
Family
ID=31901058
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1237891U Expired - Lifetime JP2505837Y2 (en) | 1991-03-07 | 1991-03-07 | Information recording device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2505837Y2 (en) |
-
1991
- 1991-03-07 JP JP1237891U patent/JP2505837Y2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04111016U (en) | 1992-09-28 |
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