JPS61170941A - Photomagnetic recording, reproducing, and erasing device - Google Patents

Abstract

PURPOSE:To monitor accurately the quantity of a laser beam by providing a feeding means which moves a head carrier and a recording medium relatively, and making the center axis which connects the S and N magnetic poles of a permanent magnet hollow and running an optical fiber therein. CONSTITUTION:The feeding means 4 shifts the head carriage and recording medium 1 in relative position to put the optical axis off the surface of the recording medium or remove the recording medium 1, and then laser light converged originally on the surface of the recording medium is all photodetected by a photoelectric element 18 through an optical fiber 18 through an optical fiber 31 penetrating the permanent magnet 30 and converted into an electric signal, which is monitored. Thus, the quantity of the light is monitored every time the recording medium is loaded or unloaded or at optional desired time when the quantity of laser light is measured. Further, the quantity of the laser light is measured at distance from the recording medium, which is therefore prevented from being exposed when light energy for recording or erasure is set.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は光磁気記録再生消去装置に関し、特に記録媒
体面上のレーザ光量を監視するレーザ光量モニタ装置の
改良に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magneto-optical recording/reproducing/erasing device, and more particularly to an improvement of a laser light amount monitoring device for monitoring the amount of laser light on the surface of a recording medium.

〔従来の技術〕[Conventional technology]

半導体レーザを光源として用いる光磁気記録再生消去装
置においてレーザ出射光量をモニタする方法としてレー
ザ後射光を利用する方法が一般的に用いられている。第
２図は例えば特開昭５１−２９８２１号公報（特許第１
０５３８２０号）に開示された従来の光磁気記録再生消
去装置に係るレーザ光量モニタ装置の構成図であり、図
において、１１は半導体レーザ、１２．１３は光学手段
、１７はレーザ段等を機械的に結合するヘッドキャリッ
ジ、１は記録媒体たるディスク、４はへノドキャリノジ
３と記録媒体１とのレーザ光軸に直交する方向での相対
的位置関係を変化させる送り手段である。2. Description of the Related Art In magneto-optical recording, reproducing and erasing devices that use a semiconductor laser as a light source, a method using back-emitted laser light is generally used as a method of monitoring the amount of laser emitted light. Figure 2 shows, for example, Japanese Patent Application Laid-Open No. 51-29821 (Patent No.
053820) is a configuration diagram of a laser light amount monitoring device related to a conventional magneto-optical recording/reproducing/erasing device. 1 is a disk which is a recording medium; 4 is a feeding means for changing the relative positional relationship between the henno carriage 3 and the recording medium 1 in a direction perpendicular to the laser optical axis.

次に動作について説明する。Next, the operation will be explained.

半導体レーザは一般に前後２方向にレーザビームを放射
しており、この２方向のビーム強さく光量）は互いに比
例関係にある。図の半導体レーザ１１の一端より出射さ
れたレーザビーム１７（以下主ビームという）は光学手
段１２．１３によりディスク面ｌ上に集光されて、この
図においてはディスク１を透過した光が第１の光電変換
素子１６に入り、電気信号に変換される。これは透過光
のモニタである。A semiconductor laser generally emits a laser beam in two directions, front and rear, and the beam intensities (light amounts) in these two directions are proportional to each other. A laser beam 17 (hereinafter referred to as the main beam) emitted from one end of the semiconductor laser 11 in the figure is focused onto the disk surface l by the optical means 12.13, and in this figure, the light transmitted through the disk 1 is the first beam. The signal enters the photoelectric conversion element 16 and is converted into an electrical signal. This is a transmitted light monitor.

一方、半導体レーザ１１の他の一端より放射されたレー
ザビーム１９（以下後射光という）を第２の光電変換素
子２０で受光して電気信号に変換することにより、この
方向のレーザビームの強さをモニタすることができ、こ
の後射光は主ビームと比例関係にあるから、これにより
主ビームの強さをモニタできることになる。On the other hand, the laser beam 19 emitted from the other end of the semiconductor laser 11 (hereinafter referred to as after-emission light) is received by the second photoelectric conversion element 20 and converted into an electric signal, thereby increasing the intensity of the laser beam in this direction. Since this after-emission light is in a proportional relationship with the main beam, it is possible to monitor the intensity of the main beam.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

従来の光磁気記録再生消去装置におけるレーザ光量モニ
タ装置は以上のように後射光によって主ビームの強さを
モニタしているので、記録媒体上に集光されるレーザ光
量は後射光を介して間接的にしかモニタされない。従っ
てほこり、ゴミなどの影響で光学手段１２．１３の透過
率が変化した場合、記録媒体面上に集光され名主ビーム
１７と後射光１９の光量と比例関係が成り立たず、モニ
タ出力は媒体面上のレーザ光量を正しく示していないこ
とになる。また第２の光電変換素子２０の受光面の寸法
が半導体レーザ１１のチップの寸法より大きい場合、光
学手段１２．１３その他による散乱光がレーザチップ１
１を飛び越えて第２の光電変換素子２０の受光面に戻る
こともあり、この場合もモニタ出力と主ビームの光量と
の比例関係は崩れる。このため従来は記録媒体１を除去
して、そのレーザビーム集光点に第３の光電変摸索　　
　　　−子（図示せず）を挿入し、実際の主ビーム光量
を較正することが必要で、その操作が繁雑なだけでなく
、測定の安定性にも問題があった。As described above, the laser light intensity monitoring device in the conventional magneto-optical recording/reproducing/erasing device monitors the intensity of the main beam using the back-emission light, so the amount of laser light focused on the recording medium is indirectly controlled via the back-emission light. only monitored. Therefore, if the transmittance of the optical means 12 or 13 changes due to the influence of dust or dirt, the light will be focused on the surface of the recording medium, and the light quantity of the main beam 17 and the after-emission beam 19 will not be proportional to each other, and the monitor output will be This means that the amount of laser light on the surface is not shown correctly. Further, when the dimensions of the light receiving surface of the second photoelectric conversion element 20 are larger than the dimensions of the chip of the semiconductor laser 11, the scattered light by the optical means 12, 13 and others is
1 and return to the light receiving surface of the second photoelectric conversion element 20, and in this case as well, the proportional relationship between the monitor output and the light amount of the main beam collapses. For this reason, in the past, the recording medium 1 was removed and a third photoelectric transformer was installed at the laser beam convergence point.
It is necessary to insert a probe (not shown) and calibrate the actual light intensity of the main beam, which not only is a complicated operation but also poses a problem in the stability of measurement.

この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、特に光磁気効果により記録再生消去を行ない
、その信号品位が記録媒体面上のレーザ光量に大きく依
存する光磁気記録再生消去装置において、記録媒体面上
の主ビームの光量を安定かつ簡便にモニタできる光磁気
記録再生消去装置を提供することを目的とする。This invention was made in order to solve the above-mentioned problems. In particular, magneto-optical recording, reproduction and erasing is performed using the magneto-optical effect, and the signal quality largely depends on the amount of laser light on the surface of the recording medium. It is an object of the present invention to provide a magneto-optical recording/reproducing/erasing device that can stably and easily monitor the amount of light of a main beam on the surface of a recording medium.

〔問題点を解決するための手段〕[Means for solving problems]

この発明に係る光磁気記録再生消去装置は光磁気記録再
生消去を行なうのに必要な外部磁界付勢手段として永久
磁石を用い、レーザ光を記録媒体面上に集光させる光学
手段と該永久磁石とを記録媒体をはさんで対向させて配
置しヘッドキャリッジにより機械的に結合して一体化し
、該ヘッドキャリッジと記録媒体とをレーザ光軸と直交
する方向に相対移動させる送り手段を設け、かつ前記永
久磁石の南北両磁極を結ぶ中心軸を中空としてその中に
光ファイバを貫通させ、記録媒体に集光されるレーザ光
を該光ファイバを介して光電変換素子に入射させ、その
光量を監視できるようにしたものである。The magneto-optical recording, reproducing and erasing device according to the present invention uses a permanent magnet as an external magnetic field urging means necessary for performing magneto-optical recording, reproducing and erasing. are placed facing each other with a recording medium in between, and are mechanically coupled and integrated by a head carriage, and a feeding means is provided for relatively moving the head carriage and the recording medium in a direction perpendicular to the laser optical axis, and The center axis connecting the north and south magnetic poles of the permanent magnet is made hollow, and an optical fiber is passed through the hollow center, and the laser beam focused on the recording medium is made to enter the photoelectric conversion element through the optical fiber, and the amount of light is monitored. It has been made possible.

〔作用〕[Effect]

この発明における光磁気記録再生消去装置においては、
上記光学手段と永久磁石とを機械的に結合したヘッドキ
ャリッジと記録媒体とを相対的に移動し、光軸を記録媒
体面から外して上記光電変換素子により記録媒体面を通
るレーザビームを受光しモニタするから、本来記録媒体
面上に集光されるべきレーザビームの光量を正確にモニ
タできる。In the magneto-optical recording/reproducing/erasing device according to the present invention,
A head carriage mechanically coupled to the optical means and a permanent magnet is moved relative to the recording medium, the optical axis is removed from the surface of the recording medium, and the photoelectric conversion element receives the laser beam passing through the surface of the recording medium. Since it is monitored, it is possible to accurately monitor the amount of light of the laser beam that should originally be focused on the surface of the recording medium.

（実施例〕 以下、この発明の一実施例を図について説明する。第１
図において、１は記録媒体、１１はレーザ光を照射する
半導体レーザ、１２．１３．１５はレーザ光を記録媒体
に集光する光学手段、１６は光学手段１３．１４．１５
を通して反射光をモニタする第１の光電変換素子、２０
は後射光をモニタする第２の光電変換素子、３０は記録
媒体１に磁界を付勢する永久磁石、３１は永久磁石３０
の南北両極を結ぶ中心軸を貫通して設けられた光ファイ
バ、１８は記録媒体面１上の光量をモニタする第３の光
電変換素子、２は記録媒体１を回転させるモータ、３は
上記光学手段１２〜１５と上記永久磁石３０とを機械的
に結合し一体化するヘッドキャリッジ、４はへウドキャ
リソジ３を光軸と直交する方向に移動させる送り手段で
ある。また、３２は回動輪であり、永久磁石３０はこの
軸を中心に回動自在に設定されている。(Example) Hereinafter, an example of the present invention will be explained with reference to the drawings.
In the figure, 1 is a recording medium, 11 is a semiconductor laser that irradiates a laser beam, 12.13.15 is an optical means that focuses the laser beam on the recording medium, and 16 is an optical means 13.14.15.
a first photoelectric conversion element that monitors reflected light through the
30 is a permanent magnet that applies a magnetic field to the recording medium 1; 31 is a permanent magnet 30;
18 is a third photoelectric conversion element that monitors the amount of light on the recording medium surface 1; 2 is a motor that rotates the recording medium 1; 3 is the optical A head carriage mechanically connects and integrates the means 12 to 15 and the permanent magnet 30, and 4 is a feeding means for moving the head carriage 3 in a direction perpendicular to the optical axis. Further, 32 is a rotating wheel, and the permanent magnet 30 is set to be rotatable around this axis.

次に動作について説明する。Next, the operation will be explained.

本実施例の光磁気記録再生消去装置は光磁気効果により
記録媒体に電気信号等を記録し再生し、もしくは消去す
るようにしたもので、光磁気記録及び消去に必要な外部
磁界を付勢するために永久磁石３０を用いている。この
永久磁石３０は記録時と消去時とでは外部磁界の向きは
逆になることが要求され、その強さは数百エルステッド
である。The magneto-optical recording/reproducing/erasing device of this embodiment records, reproduces, or erases electrical signals on a recording medium using the magneto-optical effect, and energizes an external magnetic field necessary for magneto-optical recording and erasing. A permanent magnet 30 is used for this purpose. This permanent magnet 30 is required to have an external magnetic field in opposite directions during recording and erasing, and its strength is several hundred oersteds.

この条件を満たすことは永久磁石３０を回動軸３２を中
心に回動させ、その極性を替えてやることで容易に実現
できる。Satisfying this condition can be easily achieved by rotating the permanent magnet 30 around the rotation shaft 32 and changing its polarity.

次にモニタ方法について説明すると、半導体レーザ１１
より放射された主ビーム１７は、レンズ１２、ビームス
プリンタ１５．レンズ１３の光学手段を通って記録媒体
１の面上に集光され、反射光はレンズ１３を遣った後ビ
ームスプリッタ１５によって分岐され、レンズ１４を経
て第１の光電変換素子１６に入射され、電気信号に変換
される。Next, to explain the monitoring method, the semiconductor laser 11
The main beam 17 emitted from the lens 12, the beam splinter 15. The reflected light passes through the optical means of the lens 13 and is focused onto the surface of the recording medium 1, and after passing through the lens 13, the reflected light is split by the beam splitter 15, passes through the lens 14, and enters the first photoelectric conversion element 16. converted into an electrical signal.

即ち第２図の従来装置では透過光をモニタしていたが、
本装置は透過光の代りに反射光を読み取っており、この
点に関しては何ら支障はない。In other words, the conventional device shown in Figure 2 monitors transmitted light, but
This device reads reflected light instead of transmitted light, and there is no problem in this respect.

ここで送り手段４によりヘッドキャリッジと記録媒体１
との相対的位置を変化させ、光軸を記録媒体面からはず
すか、あるいは記録媒体１を除去すると、本来記録媒体
面１上に集光されるべきレーザ光電は全て永久磁石３０
を貫通する光ファイバ３１を介して第３の光電変換素子
１８に受光され、電気信号に変換されてモニタされる。Here, the head carriage and the recording medium 1 are moved by the feeding means 4.
When the optical axis is removed from the recording medium surface by changing the relative position with respect to the recording medium surface 1, or when the recording medium 1 is removed, all of the laser photoelectric light that should originally be focused on the recording medium surface 1 is transferred to the permanent magnet 30.
The light is received by the third photoelectric conversion element 18 via the optical fiber 31 that passes through it, and is converted into an electrical signal and monitored.

図ではべ・ド１ヤリ゛・′を移動させる例を示して５゛
る力′・　　　　　−記録媒体を移動させても良いこと
は言うまでもない。Although the figure shows an example of moving the bed 1, it goes without saying that the recording medium may also be moved with a force of 5.

一般にこのような光磁気記録再生消去装置では記録媒体
を着脱するためにヘッドキャリッジを記録媒体面の外に
移動させる操作を伴うので、以上に示したような構成を
採ることで操作に繁雑をきたすことはない。かくして記
録媒体の着脱の都度、あるいは実際の主ビーム光量を計
測したい任意の時間にその光量のモニタが可能となる。Generally, in such a magneto-optical recording/reproducing/erasing device, the operation of moving the head carriage out of the surface of the recording medium is required in order to load/unload the recording medium, so adopting the configuration shown above makes the operation complicated. Never. In this way, it is possible to monitor the light amount each time the recording medium is attached or removed, or at any time when it is desired to measure the actual main beam light amount.

また第３の光電変換素子１８はヘッドキャリッジ３に固
定されているので計測の都度出し入れする必要はなく、
従って同一条件でモニタされるため、測定の安定性も向
上する。さらに本実施例装置では、レーザ光量の測定は
記録媒体から外れた所で行なわれるので、記録あるいは
消去の光エネルギーを設イドではなく、永久磁石を用い
ているので、消費電力の削減とともに装置の小型化がも
たらされる。Furthermore, since the third photoelectric conversion element 18 is fixed to the head carriage 3, there is no need to take it out and put it in each time measurement is performed.
Therefore, the stability of measurement is also improved because it is monitored under the same conditions. Furthermore, in the device of this embodiment, since the measurement of the laser light intensity is performed at a location away from the recording medium, a permanent magnet is used instead of a built-in device to provide the optical energy for recording or erasing, which reduces power consumption and improves the efficiency of the device. This results in miniaturization.

なお、上記実施例の動作では、第３の光電変換素子１８
のみを用いて光量をモニタする例を説明したが、従来例
の場合と同様後射光を第２の光電変換素子２０で実時間
モニタして短時間の光量変動に対応させ、さらに長時間
の光量変動に対して上述のモニタ出力結果でこれをで較
正するようにすれば、両者の併用によってより効果的な
レーザ光量モニタを実現できる。Note that in the operation of the above embodiment, the third photoelectric conversion element 18
Although we have explained an example in which the light intensity is monitored using only the conventional example, the second photoelectric conversion element 20 monitors the after-emission light in real time to respond to short-term light intensity fluctuations, and also monitors the light intensity over a long period of time. If the fluctuations are calibrated using the above-mentioned monitor output results, more effective laser light amount monitoring can be realized by using both together.

なお、記録媒体は上述のディスク状のものに限らず、カ
ード状あるいはテープ状のものであっても支障ない。Note that the recording medium is not limited to the disk-shaped one described above, but may also be a card-shaped or tape-shaped one.

〔発明の効果〕〔Effect of the invention〕

以上のように、この発明によれば、中心軸に光ファイバ
を貫通させた永久磁石を記録媒体をはさんで光学手段に
対向させ、さらに記録媒体面上に集光されるレーザ光を
上記光ファイバを介して光電変換素子で受光するように
構成し、かつ光学手段と永久磁石及び上記光電変換素子
を機械的に結合したヘッドキャリッジと該ヘッドキャリ
ッジと記録媒体とを光軸と直交する方向に相対移動させ
る送り手段を設けたので、はこり、ゴミなどの影響で光
学手段の透過率が変化した場合にも正確に記録媒体面上
に実際に集光されるレーザ光量を直接監視できる効果を
有し、その操作にいささかも繁雑をきたさない。As described above, according to the present invention, a permanent magnet having an optical fiber passed through its central axis is opposed to the optical means with the recording medium in between, and the laser beam focused on the surface of the recording medium is A head carriage configured to receive light with a photoelectric conversion element via a fiber and mechanically coupling an optical means, a permanent magnet, and the photoelectric conversion element, and the head carriage and a recording medium in a direction perpendicular to the optical axis. Since a feeding means for relative movement is provided, even if the transmittance of the optical means changes due to the influence of flakes, dust, etc., the amount of laser light actually focused on the surface of the recording medium can be accurately monitored directly. and its operation is not complicated at all.

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

第１図はこの発明の一実施例による光磁気記録再生消去
装置の構成図、第２図は雇来の光磁気記録再生消去装置
の構成図である。 １・・・記録媒体、３・・・ヘッドキャリフジ、４・・
・送り手段、１１・・・半導体レーザ、１２〜１４・・
・レンズ（光学手段）、１５・・・ビームスプリッタ（
光学手段）、１８・・・光電変換素子、３０・・・永久
磁石、３１・・・光ファイバ。 なお図中同一符号は同−又は相当部分を示す。FIG. 1 is a block diagram of a magneto-optical recording/reproducing/erasing apparatus according to an embodiment of the present invention, and FIG. 2 is a block diagram of a magneto-optical recording/erasing apparatus for hire. 1... Recording medium, 3... Head carriage, 4...
- Feeding means, 11... semiconductor laser, 12-14...
・Lens (optical means), 15...beam splitter (
optical means), 18... photoelectric conversion element, 30... permanent magnet, 31... optical fiber. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

【特許請求の範囲】[Claims] （１）コヒーレントな光を放射するレーザ光源と、該レ
ーザ光を記録媒体面上に集光する光学手段と、上記記録
媒体をはさんで上記光学手段に対向し上記記録媒体に垂
直な方向の外部磁界を付勢する外部磁界付勢手段と、上
記光学手段及び上記外部磁界付勢手段の両者を機械的に
結合して一体化したヘッドキャリッジと、該ヘッドキャ
リッジと上記記録媒体との、レーザ光軸に直交する方向
での相対的位置関係を変化させる送り手段とを有する光
磁気記録再生消去装置において、上記外部磁界付勢手段
は上記記録媒体に入射する光軸と同心になるように配置
された永久磁石であり、該永久磁石はその両極を通る中
心軸に貫通して設けられた光ファイバを有するとともに
、その中心軸に直交する回動軸を中心に回動自在に設け
られ、かつ記録媒体面に集光されるレーザ光を上記光フ
ァイバを介して受光する光電変換素子が上記ヘッドキャ
リッジに固定して設けられていることを特徴とする光磁
気記録再生消去装置。(1) A laser light source that emits coherent light, an optical means that focuses the laser light onto the recording medium surface, and a laser light source that faces the optical means with the recording medium in between and that is perpendicular to the recording medium. an external magnetic field energizing means for energizing an external magnetic field; a head carriage mechanically coupling and integrating both the optical means and the external magnetic field energizing means; and a laser beam between the head carriage and the recording medium. In the magneto-optical recording/reproducing/erasing device, the external magnetic field energizing means is arranged to be concentric with the optical axis incident on the recording medium. The permanent magnet has an optical fiber extending through a central axis passing through both poles of the permanent magnet, and is rotatable about a rotation axis perpendicular to the central axis, and 1. A magneto-optical recording, reproducing and erasing device, characterized in that a photoelectric conversion element that receives laser light focused on a surface of a recording medium via the optical fiber is fixedly provided on the head carriage.