JPH0191343A - Output control method for semiconductor laser of multibeam magneto-optical pickup - Google Patents
Output control method for semiconductor laser of multibeam magneto-optical pickupInfo
- Publication number
- JPH0191343A JPH0191343A JP62168093A JP16809387A JPH0191343A JP H0191343 A JPH0191343 A JP H0191343A JP 62168093 A JP62168093 A JP 62168093A JP 16809387 A JP16809387 A JP 16809387A JP H0191343 A JPH0191343 A JP H0191343A
- Authority
- JP
- Japan
- Prior art keywords
- semiconductor laser
- output
- laser
- recording
- controlled
- 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
- 239000004065 semiconductor Substances 0.000 title claims abstract description 93
- 238000000034 method Methods 0.000 title claims description 4
- 238000005070 sampling Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
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
- G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
- G11B19/02—Control of operating function, e.g. switching from recording to reproducing
Landscapes
- Optical Head (AREA)
Abstract
Description
【発明の詳細な説明】
(技術分野)
本発明はマルチビーム光磁気ピックアップの半導体レー
ザ出力制御方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a semiconductor laser output control method for a multi-beam magneto-optical pickup.
(従来の技術)
光磁気ディスクは消去、記録、再生という;3つのモー
ドで情報の書き込みが完了する。これを1つの半導体レ
ーザを有する光磁気ピックアップで行なうと、光磁気デ
ィスク上の同じ場所を3回レーザビームでトレースしな
ければならず非常に時間がかかる。そこで高速の消去、
記録、再生を行なうために複数の光磁気ピックアップや
複数の半導体レーザを有する光磁気ピックアップを用い
ることが特開昭60−47238号公報等で提案されて
いるが、これには複数の半導体レーザの出力をそれぞれ
所定の基準値に制御することが必要である。(Prior Art) Writing of information to a magneto-optical disk is completed in three modes: erasing, recording, and reproduction. If this is done with a magneto-optical pickup having one semiconductor laser, the same location on the magneto-optical disk must be traced three times with a laser beam, which is very time consuming. Therefore, high-speed erasing,
The use of a magneto-optical pickup having a plurality of magneto-optical pickups or a plurality of semiconductor lasers for recording and reproduction has been proposed in Japanese Patent Application Laid-Open No. 60-47238, etc.; It is necessary to control each output to a predetermined reference value.
(目 的)
本発明はこのような点に鑑み、複数の半導体レーザの出
力を制御できるマルチビーム光磁気ピックアップの半導
体レーザ出力制御方法を提供することを目的とする。(Objective) In view of the above points, an object of the present invention is to provide a semiconductor laser output control method for a multi-beam magneto-optical pickup that can control the output of a plurality of semiconductor lasers.
(構 成)
本発明は消去記録用の第1の半導体レーザと再生用の第
2の半導体レーザとが並んだ半導体レーザアレイを有す
る光磁気ピックアップにおいて、消去モードではアドレ
ス読み取り時に上記第1の半導体レーザを消し上記第2
の半導体レーザの出力を基準値に制御して保持し、消去
領域において上記第1及び第2の半導体レーザを点灯し
て上記第1の半導体レーザの出力を基準値に制御し、記
録モードではアドレス読み取り時及び記録領域において
上記第1の半導体レーザが点灯していないときに上記第
2の半導体レーザの出力を基準値に制御して保持し、ア
ドレス読み出し後レーザビームが記録領域に到達するま
での期間上記第1の半導体レーザを点灯し上記第1及び
第2の半導体レーザが点灯した状態で上記第1の半導体
レーザの出力を基準値に制御して保持し、再生モードで
は上記第2の半導体レーザの出力を基準値に制御する。(Structure) The present invention provides a magneto-optical pickup having a semiconductor laser array in which a first semiconductor laser for erasing and recording and a second semiconductor laser for reproducing are arranged side by side. Turn off the laser and
The output of the semiconductor laser is controlled and held at a reference value, the output of the first semiconductor laser is controlled to be the reference value by lighting the first and second semiconductor lasers in the erase area, and the output of the first semiconductor laser is controlled to the reference value in the recording mode. During reading and when the first semiconductor laser is not lit in the recording area, the output of the second semiconductor laser is controlled and held at the reference value, and the output of the second semiconductor laser is controlled and held at the reference value until the laser beam reaches the recording area after reading the address. During the period, the first semiconductor laser is turned on, and with the first and second semiconductor lasers turned on, the output of the first semiconductor laser is controlled and held at the reference value, and in the reproduction mode, the second semiconductor laser is turned on. Control the laser output to a reference value.
以下図面を参照して本発明の詳細な説明する。The present invention will be described in detail below with reference to the drawings.
第3図は光磁気ピックアップの一例を示す。FIG. 3 shows an example of a magneto-optical pickup.
半導体レーザアレイ11は2つの半導体レーザ12゜1
3を100μmの間隔にて隣接して配列したものであり
、2つの半導体レーザ12,13はレーザビームを略同
じ方向に放射する。この半導体レーザ12,13から前
方に放射されたレーザビームはカップリングレンズ14
を介してビームスプリッタ15で反射され。The semiconductor laser array 11 includes two semiconductor lasers 12°1
The two semiconductor lasers 12 and 13 emit laser beams in substantially the same direction. The laser beam emitted forward from the semiconductor lasers 12 and 13 is transmitted through a coupling lens 14.
and is reflected by the beam splitter 15.
対物レンズ16により光磁気ディスク17上に小さなス
ポットSl、S2として照射される。半導体レーザ12
は消去記録用として用いられて半導体レーザ13は再生
用として用いられ、スポットSl、S2の間隔は例えば
50μmである。光磁気ディスク17で反射された各レ
ーザビームは対物レンズ16、ビームスプリッタ15を
介して検出系でそれぞれ検出される。The objective lens 16 illuminates the magneto-optical disk 17 as small spots Sl and S2. Semiconductor laser 12
is used for erasing and recording, and the semiconductor laser 13 is used for reproducing, and the interval between the spots Sl and S2 is, for example, 50 μm. Each laser beam reflected by the magneto-optical disk 17 is detected by a detection system via an objective lens 16 and a beam splitter 15.
また光磁気ディスク17は磁気ヘッド18により磁界が
印加され、この磁気ヘッド18と上記光学系を含む光磁
気ピックアップが光磁気ディスク17の半径方向へ移動
すると共に光磁気ディスク17が回転して光磁気ディス
ク17上の情報の消去、記録、再生が行なわれる。Further, a magnetic field is applied to the magneto-optical disk 17 by a magnetic head 18, and the magneto-optical pickup including the magnetic head 18 and the above-mentioned optical system moves in the radial direction of the magneto-optical disk 17, and the magneto-optical disk 17 rotates. Information on the disk 17 is erased, recorded, and reproduced.
第1図は本発明の実施に使用した装置の一例を示す。こ
の装置は上記半導体レーザ12,13の出力を制御する
ものであり、半導体レーザ12,13の後方に射出され
たレーザビームは1つのフォトダイオードからなる光検
出器19で検出されて増幅器20で増幅される。この増
幅器20の出力は比較器21,22にて基準電圧Vre
f 1 、 Vref 2と比較され、その誤差出力は
それぞれローパスフィルタ23.24を経てサンプリン
グホールド回路25.26でタイミング発生回路27か
らのタイミング信号TI、T2によりサンプリングホー
ルドされる。半導体レーザ駆動回路28゜29はサンプ
リングホールド回路25.26の出力信号により半導体
レーザ12,13の駆動電流を制御し、半導体レーザ1
2,13の光出力が常に基準電圧Vrefl。FIG. 1 shows an example of an apparatus used to carry out the present invention. This device controls the output of the semiconductor lasers 12 and 13, and the laser beam emitted backward from the semiconductor lasers 12 and 13 is detected by a photodetector 19 consisting of one photodiode and amplified by an amplifier 20. be done. The output of this amplifier 20 is converted to a reference voltage Vre by comparators 21 and 22.
It is compared with f 1 and Vref 2, and the error outputs are sampled and held by the timing signals TI and T2 from the timing generation circuit 27 in sampling and holding circuits 25 and 26 through low-pass filters 23 and 24, respectively. The semiconductor laser drive circuits 28 and 29 control the drive currents of the semiconductor lasers 12 and 13 using the output signals of the sampling and hold circuits 25 and 26, and control the drive currents of the semiconductor lasers 12 and 13.
The optical outputs 2 and 13 are always at the reference voltage Vrefl.
Vref2に相当する値に制御される。また半導体し一
ザ駆動回路28は変調入力により半導体レーザ12をオ
ン/オフさせる。It is controlled to a value corresponding to Vref2. Further, a semiconductor laser drive circuit 28 turns on/off the semiconductor laser 12 by modulation input.
次にこの装置を第2図(イ)に示す動作状態に従って説
明する。Next, this device will be explained according to the operating state shown in FIG. 2(a).
再生用半導体レーザ13はいかなる状態でも常に点灯状
態にある。スタンバイ時は消去記録用半導体レーザ12
が消灯状態になり、フォトダイオード19には半導体レ
ーザ13の出力のみが入射する。この時タイミング信号
T2は高レベルとなっており、半導体レーザ13の出力
が基準電圧Vref2と等しくなるように制御される。The reproducing semiconductor laser 13 is always lit in any state. Semiconductor laser 12 for erasing and recording during standby
is turned off, and only the output of the semiconductor laser 13 is incident on the photodiode 19. At this time, the timing signal T2 is at a high level, and the output of the semiconductor laser 13 is controlled to be equal to the reference voltage Vref2.
消去モードではタイミング信号T2は第2図(ロ)に示
すようにアドレス読み取り時に高レベルとなり、サンプ
リングホールド回路26はローパスフィルタ24の出力
をサンプリングしてその値をタイミング信号T2が低レ
ベルになったときに保持し、半導体レーザ13の出力が
基Kl圧Vref2に対応する値に制御される。半導体
レーザ駆動回路28は第2図(ハ)に示すような変調入
力により半導体レーザ12を消去領域においては点灯状
態とし、アドレス読み取り領域においては消灯状態とす
る。タイミング信号T1が第2図(ニ)に示すように高
レベルの時にローパスフィルタ23の出力がサンプリン
グホールド回路25でサンプリングされ、その値はタイ
ミング信号T1が低レベルとなったときにサンプリング
ホールト回路25で保持され、半導体レーザ12の出力
が基準電圧Vref 1に相当する値に制御される。半
導体レーザ12の出力制御時には半導体レーザ13が点
灯しているから、比較器21.22には2個の半導体レ
ーザ12,13の出力の合成された信号に相当する入力
信号が入るが、半導体レーザ13の出力は一定に制御さ
れている為、基準電圧Vreflは予め所定の値に基準
電圧Vref2を加算した値に設定しておけば良い。半
導体レーザ12.13は消去時には両方とも点灯し、情
報の消去の確認が行なわれる。In the erase mode, the timing signal T2 goes to a high level when reading an address, as shown in FIG. The output of the semiconductor laser 13 is controlled to a value corresponding to the base Kl pressure Vref2. The semiconductor laser drive circuit 28 turns on the semiconductor laser 12 in the erase area and turns it off in the address reading area by modulating input as shown in FIG. 2(C). As shown in FIG. 2(D), the output of the low-pass filter 23 is sampled by the sampling hold circuit 25 when the timing signal T1 is at a high level, as shown in FIG. 25, and the output of the semiconductor laser 12 is controlled to a value corresponding to the reference voltage Vref1. Since the semiconductor laser 13 is on when controlling the output of the semiconductor laser 12, an input signal corresponding to the combined output of the two semiconductor lasers 12 and 13 is input to the comparators 21 and 22. 13 is controlled to be constant, the reference voltage Vrefl may be set in advance to a value obtained by adding the reference voltage Vref2 to a predetermined value. Both semiconductor lasers 12 and 13 are turned on during erasing to confirm erasure of information.
記録モードでは半導体レーザ13の出力制御はアドレス
読み取り時には消去時と同様である。記録領域において
は半導体レーザ12が点灯状態にない時、つまり情報の
記録を行なっていないときタイミング信号T2が高レベ
ルになり、半導体レーザ12が点灯状態にあるときにタ
イミング(ilT2が低レベルになる。サンプリングホ
ールド回路26はタイミング信号T2が高レベルの時ロ
ーパスフィルタ24の出力をサンプリングし、その値を
タイミング信号T2が低レベルの時保持し、半導体レー
ザ13の出力制御が行なわれる。タイミング信号T1は
第2図(ニ)に示すようにアドレス読み取り後光磁気ピ
ックアップのレーザビームが記録領域に達するまでの間
高レベルとなり、第2図(ハ)に示すような変調入力に
より半導体レーザ】2が点灯する。この場合比較器21
.22には2個の半導体レーザ12,13の出力を合成
した信号に相当する入力信号が入る消去時と同様に半導
体レーザの出力制御が行なわれることにより、半導体レ
ーザ12の出力が制御され、タイミング信号T1が記録
時に低レベルになってサンプリングホールド回路25が
保持状態になり、半導体レーザ12の出力が一定に制御
される。この状態で変調入力により情報信号で半導体レ
ーザ12がオン/オフされて光磁気ディスク17に情報
の記録が行なおれる5
再生モードではスタンバイ時と同様に半導体レーザ13
の出力が制御され、半導体レーザ12は消灯する。In the recording mode, the output control of the semiconductor laser 13 is the same when reading an address as when erasing. In the recording area, when the semiconductor laser 12 is not in the lighting state, that is, when information is not being recorded, the timing signal T2 is at a high level, and when the semiconductor laser 12 is in the lighting state, the timing signal T2 is at a low level. The sampling and hold circuit 26 samples the output of the low-pass filter 24 when the timing signal T2 is at a high level, holds the value when the timing signal T2 is at a low level, and controls the output of the semiconductor laser 13.The output of the semiconductor laser 13 is controlled by the timing signal T1. As shown in Figure 2 (D), after reading the address, the laser beam of the magneto-optical pickup remains at a high level until it reaches the recording area, and due to the modulation input as shown in Figure 2 (C), the semiconductor laser [2] Lights up.In this case, comparator 21
.. 22 receives an input signal corresponding to a signal obtained by combining the outputs of the two semiconductor lasers 12 and 13. The output of the semiconductor laser 12 is controlled by controlling the output of the semiconductor laser in the same manner as during erasing, and the timing During recording, the signal T1 becomes low level, the sampling hold circuit 25 enters a holding state, and the output of the semiconductor laser 12 is controlled to be constant. In this state, the semiconductor laser 12 is turned on/off by the information signal by the modulation input, and information is recorded on the magneto-optical disk 17.5 In the playback mode, the semiconductor laser 13
The output of the semiconductor laser 12 is controlled and the semiconductor laser 12 is turned off.
(効 果)
以上のように本発明によれば消去記録用の第1の半導体
レーザと再生用の第2の半導体レーザとが並んだ半導体
レーザアレイを有する光磁気ピックアップにおいて、消
去モードではアドレス読み取り時に上記第1の半導体レ
ーザを消し上記第2の半導体レーザの出力を基準値に制
御して保持し、消去領域において上記第1及び第2の半
導体レーザを点灯して上記第1の半導体レーザの出力を
基準値に制御し、記録モードではアドレス読み取り時及
び記録領域において上記第1の半導体レーザが点灯して
いないときに上記第2の半導体レーザの出力を基準値に
制御して保持し、アドレス読み出し後レーザビームが記
録領域に到達するまでの期間上記第1の半導体レーザを
点灯し上記第1及び第2の半導体レーザが点灯した状態
で上記第1の半導体レーザの出力を基準値に制御して保
持し、再生モードでは上記第2の半導体レーザの出力を
基準値に制御するので、複数の半導体レーザの出力を制
御することができて高速の消去、記9.再生が可能とな
る。(Effects) As described above, according to the present invention, in a magneto-optical pickup having a semiconductor laser array in which a first semiconductor laser for erasing and recording and a second semiconductor laser for reproducing are arranged, it is possible to read an address in the erasing mode. At times, the first semiconductor laser is turned off, the output of the second semiconductor laser is controlled and held at a reference value, and the first and second semiconductor lasers are turned on in the erasing area to control the output of the first semiconductor laser. The output is controlled to a reference value, and in the recording mode, the output of the second semiconductor laser is controlled and held at the reference value when reading an address and when the first semiconductor laser is not lit in the recording area. After reading, the first semiconductor laser is turned on for a period until the laser beam reaches the recording area, and the output of the first semiconductor laser is controlled to a reference value while the first and second semiconductor lasers are turned on. In the playback mode, the output of the second semiconductor laser is controlled to the reference value, so the output of a plurality of semiconductor lasers can be controlled and erased at high speed. Playback becomes possible.
第1図は本発明の実施に用いた装置の一例を示すブロッ
ク図、第2図は間装はのタイミングチャート、第3図は
光磁気ピックアップの一例を示す図である。
12.13・・・半導体レーザ、19・・・光検出器、
21,22・・・比較器、23.24・・・ローパスフ
ィルタ、25,26・・・サンプリングホールド回路、
27・・・タイミング発生回路、28.29・・・半導
体レーザ駆動回路。FIG. 1 is a block diagram showing an example of a device used to implement the present invention, FIG. 2 is a timing chart of an interlayer, and FIG. 3 is a diagram showing an example of a magneto-optical pickup. 12.13... Semiconductor laser, 19... Photodetector,
21, 22... Comparator, 23.24... Low pass filter, 25, 26... Sampling hold circuit,
27... Timing generation circuit, 28.29... Semiconductor laser drive circuit.
Claims (1)
導体レーザとが並んだ半導体レーザアレイを有する光磁
気ピックアップにおいて、消去モードではアドレス読み
取り時に上記第1の半導体レーザを消し上記第2の半導
体レーザの出力を基準値に制御して保持し、消去領域に
おいて上記第1及び第2の半導体レーザを点灯して上記
第1の半導体レーザの出力を基準値に制御し、記録モー
ドではアドレス読み取り時及び記録領域において上記第
1の半導体レーザが点灯していないときに上記第2の半
導体レーザの出力を基準値に制御して保持し、アドレス
読み出し後レーザビームが記録領域に到達するまでの期
間上記第1の半導体レーザを点灯し上記第1及び第2の
半導体レーザが点灯した状態で上記第1の半導体レーザ
の出力を基準値に制御して保持し、再生モードでは上記
第2の半導体レーザの出力を基準値に制御することを特
徴とするマルチビーム光磁気ピックアップの半導体レー
ザ出力制御方法。In a magneto-optical pickup having a semiconductor laser array in which a first semiconductor laser for erasure recording and a second semiconductor laser for reproduction are arranged side by side, in the erase mode, the first semiconductor laser is turned off when reading an address, and the second semiconductor laser is turned off when reading an address. The output of the semiconductor laser is controlled and held at the reference value, the first and second semiconductor lasers are turned on in the erase area, the output of the first semiconductor laser is controlled to the reference value, and the address is read in the recording mode. The output of the second semiconductor laser is controlled and held at the reference value when the first semiconductor laser is not lit in the recording area, and the period after the address is read until the laser beam reaches the recording area. With the first semiconductor laser turned on and the first and second semiconductor lasers turned on, the output of the first semiconductor laser is controlled and held at a reference value, and in the reproduction mode, the output of the second semiconductor laser is A semiconductor laser output control method for a multi-beam magneto-optical pickup, characterized in that the output of the multi-beam magneto-optical pickup is controlled to a reference value.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62168093A JPH0191343A (en) | 1987-07-06 | 1987-07-06 | Output control method for semiconductor laser of multibeam magneto-optical pickup |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62168093A JPH0191343A (en) | 1987-07-06 | 1987-07-06 | Output control method for semiconductor laser of multibeam magneto-optical pickup |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0191343A true JPH0191343A (en) | 1989-04-11 |
Family
ID=15861715
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP62168093A Pending JPH0191343A (en) | 1987-07-06 | 1987-07-06 | Output control method for semiconductor laser of multibeam magneto-optical pickup |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0191343A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH03183034A (en) * | 1989-12-11 | 1991-08-09 | Fujitsu Ltd | Semiconductor laser control circuit for optical disk device |
EP0713215A2 (en) * | 1994-11-16 | 1996-05-22 | Canon Kabushiki Kaisha | Optical information recording and/or reproducing apparatus and method with auto power control function for two light sources |
-
1987
- 1987-07-06 JP JP62168093A patent/JPH0191343A/en active Pending
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH03183034A (en) * | 1989-12-11 | 1991-08-09 | Fujitsu Ltd | Semiconductor laser control circuit for optical disk device |
JP2745747B2 (en) * | 1989-12-11 | 1998-04-28 | 富士通株式会社 | Optical disk drive |
EP0713215A2 (en) * | 1994-11-16 | 1996-05-22 | Canon Kabushiki Kaisha | Optical information recording and/or reproducing apparatus and method with auto power control function for two light sources |
EP0713215A3 (en) * | 1994-11-16 | 1996-10-09 | Canon Kk | Optical information recording and/or reproducing apparatus and method with auto power control function for two light sources |
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