JPS58100245A - Controller for quantity of light of optical recording and reproducing device - Google Patents
Controller for quantity of light of optical recording and reproducing deviceInfo
- Publication number
- JPS58100245A JPS58100245A JP56199830A JP19983081A JPS58100245A JP S58100245 A JPS58100245 A JP S58100245A JP 56199830 A JP56199830 A JP 56199830A JP 19983081 A JP19983081 A JP 19983081A JP S58100245 A JPS58100245 A JP S58100245A
- Authority
- JP
- Japan
- Prior art keywords
- pulse
- comparator
- laser
- light
- counter
- 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
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
- G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
- G11B7/126—Circuits, methods or arrangements for laser control or stabilisation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
- H01S5/068—Stabilisation of laser output parameters
- H01S5/0683—Stabilisation of laser output parameters by monitoring the optical output parameters
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optical Head (AREA)
Abstract
Description
【発明の詳細な説明】
本発明ｔまレーザ光源の斐調量を一部レベルに抑えるだ
めの光−横制御装置に関し、特に光学的に情報を記録再
生する襞直にあげる隋−４記録のだめの光パルスの強要
を制御する装置にＩＡする。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical-lateral control device for suppressing the adjustment amount of a laser light source to a certain level. IA to a device that controls the forcing of light pulses.
元ビデオディスク、光デイスクファイル装置等パルス状
信号で変調されたレーザ光束でレンズで絞り感光性媒体
ｉｃ ＋＋＠封して媒坏ケ光学的に変質させて情報ｋ
Ｍじ録する元学的隋報記録再生装置Ｖこおいては情べを
記録する元パルスの強度が震動すると簾俸の変質の度会
いあるいは変質した９Ａ城（ビット）の大きさが変化し
、１肯報のｉ１録再生特性が悪化する。一方、レーザ光
の変調強度は変調器Ｃ同一条件で駆動しても温度変４ｄ
Ｊ尋により容易に変化する。例えば半尋体レーザＫｇい
ては妃度上昇によってレーザ発光の閾値が変化し一定の
電流を供給していても発光光量が変化する。ガスレーザ
光の変調を行なう電気光学光変調’４（ＨＤ変調器）も
同様に温度変動により変調レベルが変化する。Original video disk, optical disk file device, etc. A photosensitive medium IC ++@ is sealed with a lens using a laser beam modulated with a pulsed signal and the medium is optically altered to provide information.
In this case, when the intensity of the original pulse that records the feelings trembles, the degree of alteration of the blind or the size of the altered 9A bit changes. , the i1 recording and playback characteristics of 1 positive signal deteriorate. On the other hand, the modulation intensity of the laser beam varies by 4d due to temperature even if modulator C is driven under the same conditions.
Easily changes by J fathom. For example, in the case of a half-body laser Kg, the threshold value for laser emission changes as the temperature increases, and the amount of emitted light changes even if a constant current is supplied. Similarly, the modulation level of electro-optic light modulation '4 (HD modulator) that modulates gas laser light changes due to temperature fluctuations.
従って記録媒体に対し尚冒波高品質の記録を行なうため
ｉＣは記録用元パルスの強度ｒ規定値に保つよう圧制御
する必要がある。従来この光強度の制御は主にバイアス
レベルの安定化、すなわちパルスを発生し了い弱いレー
ザ光を定常的ｖＣｉＭ生している状態での光透の制御と
いう形で行なわルていた。これだと弱い参照元を照射し
て情報を再生する際に、よ有効であるが記録時の光パル
スの強度１′よあくまで間接的にしか制御ざノＬｉよか
っｌヒ。Therefore, in order to perform high-quality recording on a recording medium, it is necessary to control the pressure of iC so as to maintain the strength r of the recording source pulse at a specified value. Conventionally, this control of the light intensity has been carried out mainly by stabilizing the bias level, that is, by controlling the light transmission in a state where a steady vCiM of weak laser light is generated after the pulse has been generated. This is very effective when reproducing information by irradiating a weak reference source, but the intensity of the optical pulse during recording can only be controlled indirectly.
また別の方法としては記録時の反射光を検出して記録光
慮を制御することも考えられているが媒体からの反射光
は媒体特性の変動の影１ｔ（ｒ５げやすくまた記録によ
る変化も太さいためこれ金利用することは必ずしもｊ適
当では／、１′い。しかもこの場合変調量の制御ｌ・よ
アナログ的なフィードバックによっているため常時記録
パルスが発生していゐならともかく間欠的にしＱｌｌ記
録動作を行なわない元ディスクファイル装置等に、ｄい
て「１ま最適な変調量の保持が困難Ｃ７」〕っ之。Another method is to control the recording light by detecting the reflected light during recording, but the reflected light from the medium is susceptible to changes in medium characteristics (r5) and is susceptible to changes due to recording. Since it is so thick, it is not necessarily appropriate to use this metal.Moreover, in this case, the amount of modulation is controlled by analog feedback, so even if recording pulses are generated all the time, it is necessary to use them intermittently. For a source disk file device etc. that does not perform recording operations, ``Difficult to maintain the optimum modulation amount C7''.
本発明はう）１フする欠課を除き、−（Ｊ欠−ＪＩＪ＋
ｃ発生する元パルスの強度をゲ定（・こ制御し、光学的
記録再生装置において高晶質１（情報の記録を可能にす
る元Ｊ制＃装置を提供しようとするものである。The present invention is applicable to -(J missing -JIJ+
The purpose of this invention is to provide an original J system device that controls the intensity of the original pulse generated and enables the recording of highly crystalline information in an optical recording/reproducing device.
以下に本発明につさ図面を参照して詳しく Ｉｖｌ明す
る。The present invention will be explained in detail below with reference to the drawings.
第１図は本栖明の光１に制御隙装置の一実４例を示すブ
ロック図である。FIG. 1 is a block diagram showing four examples of Akira Motosu's optical control gap device.
半導体レーデｌＯ：θ発光さルるレーザ光゛・エコリメ
ートレンズ１１１・こより）Ｆ行光に１１され更、Ｃ集
束レンズ１２．こよって微小なビームスポットｖｃ収ら
れｎｄ杯媒体１３上に照射さル、〉。半、・４体／−ザ
ｌＯ・０発光するレーナ尤の一郡・Ｌ光検出器１４に入
射し、元萩出器１４は九の頷ｒｃ （）を鎗）にＲ応す
る電流を出力する。Semiconductor radar 10: θ-emitted laser beam (from the ecolimate lens 111) is converted into the F-row beam, and the C-converging lens 12. As a result, a minute beam spot VC is focused and irradiated onto the second cup medium 13. Half, ・4 bodies/-the lO・0 A group of Lena's emitting light enters the L photodetector 14, and the Motohagi output device 14 outputs a current corresponding to R to the nine nods rc (). do.
半導体レーザ１０に（・まバイアス−流供給回路２０エ
リ弱い一定レベルの発光にさせるためのバイアス電流が
常時供給される。記塾状態となり記録データパルス１０
１が人力すると変調：奮＠ ＝Ｉ’ｌ路２１は半導体レ
ーザ１０に記録用光パルスを発生させるだめのパルス電
流を供給する。６己碌用パルス電流の大きさは電流制御
回路２２によりｉｔｔ制御てれる。半導体レーザ１０の
特性が変化しなければ記、纜用パルス電流の大きさを一
定に夫つこと（・こより常に同じ強さの記録用元パルス
かう６生ｆｂばずであるが、実際ｖｃは半導体レーザ１
０が個々に特性のばらつきがある上に温度変動経時斐化
尋により同じ大きさの電流で供給しても発生する元パル
スの強度は変化する。このため光検出器１４で検出する
光パルスのｌｌ１ｌｉさが常に規定値付近に株たれるよ
うにパルス電流の大きさを制御する必要がある。光検出
器１４よりの出力成流は抵抗３０（先よって受けられ信
号線１１０に元パルス強紋に対応するパルス電圧ＢＤ１
に発生する。このパルス電圧、ユ第１の比較器２３によ
り記録用光パルス−１ｊｉｉ 度Ｊ）１限を規定する第
１の規定゛延圧Ｅ１ と比較される。A bias current is constantly supplied to the semiconductor laser 10 to cause the bias current supply circuit 20 to emit light at a weak constant level.
When 1 is input manually, the modulation: I'l path 21 supplies a pulse current to the semiconductor laser 10 to generate a recording optical pulse. The magnitude of the pulse current for self-enhancement is controlled by the current control circuit 22. If the characteristics of the semiconductor laser 10 do not change, the magnitude of the main pulse current should be kept constant. Semiconductor laser 1
In addition to variations in the characteristics of individual pulses, the intensity of the original pulse generated changes even if the same amount of current is supplied due to temperature fluctuations and changes in temperature over time. For this reason, it is necessary to control the magnitude of the pulse current so that ll1li of the optical pulse detected by the photodetector 14 is always near the specified value. The output current from the photodetector 14 is received by a resistor 30 (first, and a pulse voltage BD1 corresponding to the original pulse intensity is applied to the signal line 110).
occurs in This pulse voltage is compared by a first comparator 23 with a first regulation "rolling pressure E1" which defines a limit of -1jii degree J) of the recording optical pulse.
記録データパルス１０１がオン時即ち元パルス発生５一
時にパルス電圧ＥＤの大きさが第１の硯定酸圧Ｅ１を超
えると７リツプフロツプ２５がセットさするっ逆にパル
ス電圧ＢＤが第１の規定・冗広Ｅ１ を超えなげればフ
リ、プフロップ２５（はリセット８ルだままである。一
方、第２の比べ、；（： ２４まパルス電圧ＥＤ と
光パルス強度の上限を規定するｌＡ２の呪定眠圧Ｅ２の
大ささ勿比較し、光パルス発生時にパルス電圧ｇＤの大
きさが第２の規定邂圧Ｅ２を超えると７リツプフロツプ
２６ｉセツトする。When the recording data pulse 101 is on, that is, when the original pulse is generated, when the magnitude of the pulse voltage ED exceeds the first constant acid pressure E1, the 7 lip-flop 25 is set.・If Jauhiro E1 is not exceeded, the flop 25 remains reset to 8. On the other hand, the second comparison; Of course, the magnitude of the sleep pressure E2 is compared, and if the magnitude of the pulse voltage gD exceeds the second specified pressure E2 when a light pulse is generated, the 7 lip-flop 26i is set.
１つの元パルスの発生が終了しチこ電気で７リツプフロ
ツプ２６がセットされているとカウンタ２７はカウント
アツプされそ、Ｄｍ持する値を１つ減する。−万、同じ
ときにフリップ７０ツブ２５がセット名Ｉしていなげれ
ばカウンタ２７・愼カクントアップされ値を１つ増加す
る。ｄＩＪら１つの元パルス発生時にその元パルスのＩ
ＩＭ （ｔｆ、が第１の規定値に達していなければカウ
ンタ２７ｊ：カウントアツプされ、逆に元パルスの値反
が第２の規定（１’ｘ超えていルばカウンタ２７はカウ
ントダウン姑ル６゜１回の冗パルスの発生に刈しカウン
タ２７の値すよ６−
せいぜいｌだけ変化するのみで／１１）り修正ニー°と
しては一見少く思われるが、ｆｄ報Ｍｅ録時ＩＴ（は致
ゴ乃至以千）つ光パルスが周期０，１μＳ〜１．１１ｓ
、１％度で兄生するため十分な大きざの修正が極めて短
時間に行なわれることになる。When the generation of one original pulse is completed and the 7-lip flop 26 is set by the electric current, the counter 27 is counted up and the value held by Dm is decreased by one. - 10,000, if the flip 70 knob 25 does not change the set name I at the same time, the counter 27 is incremented and its value is increased by one. When one original pulse is generated such as dIJ, the I of the original pulse is
If IM (tf) has not reached the first specified value, the counter 27j counts up, and if the value of the original pulse exceeds the second specified value (1'x), the counter 27 counts down by 6°. The value of the cutting counter 27 changes by at most 6-1/11) per occurrence of one redundant pulse, which may seem small at first glance as a correction need, but when recording the fd information 1,000) optical pulses with a period of 0.1μS to 1.11s
, sufficient size corrections can be made in an extremely short time to achieve a 1% degree increase.
カウンタ２７の出力はディジタルアナログ、炙浪益２８
に擾続され、ディジタルアナログ”Ｋｆｓ器２Ｂは記録
用元パルスのｇ１度卵重５変調、λを１’ｉ’ｌ １卸
、？゛イ）価号１１）２Ｑ４流制御回路２２に入力する
６ １＃ｔ ｔａｉｌイ１回Ｉ各２２ ｖｉ匿−号１
０２にＬ６じて半導体レーザ１０＜供給するパルス電流
の大き゛さン（化させ元パルスの１度を規定値範囲内に
保つように働く。を鴫に分るようにカウンタ２７はディ
ジタル【で、わる計数！１占を保持すｂからアナログ１
ル圧のサンプルホールドＩｌ−！ｌ路のるいは積分回路
の」二うに時ｒＦ＋１経過によるレベル変動の恐ルは全
くなく、焼時間再生動作のみで記録が行なわれない場よ
−Ｃも安定に以前のパルス′亀流の大ささが保持ざ几る
。The output of the counter 27 is digital/analog.
The digital analog "Kfs device 2B modulates the original pulse for recording by 1 degree and 5 degrees, and inputs λ to the 2Q4 flow control circuit 22. 6 1#t tail once I each 22 vi hidden number 1
02, the magnitude of the pulse current supplied to the semiconductor laser 10 is changed to L6, and it works to keep the original pulse within a specified value range.As you can clearly see, the counter 27 is a digital Correct counting! Analog 1 from b that holds 1 divination
sample hold Il-! There is no fear of level fluctuations due to the passage of time rF+1 in the loop or integrator circuit, and when recording is not performed only by reproducing the burning time, the magnitude of the previous pulse 'torque current' is also stable. Sasaga is held.
第２図は第１図に示した装置ＩＩｔ（ＤＩ助作ｋｍ明す
＠ための各部の情号波形の例を示す図であるうお譚デー
タパルス１０１がオンとなると半導体レーザ１０より元
パルスが発生し光検出器１４よりの光検出＋９．鑞によ
り１□５号ｈＭ１１０４でパルス電圧Ｅ９が発生する。FIG. 2 is a diagram showing an example of the information waveform of each part of the device IIt shown in FIG. A pulse voltage E9 is generated in the 1□ No. 5 hM1104 due to the photodetection by the photodetector 14 +9.
、時刻ｔ１ に北い−Ｃｊ５生したパルス電圧ＥＤが
第１の規定＋Ｌｆ、圧Ｅ１ より低いレベルであると
きはカウンタ２７は１つカウントアツプｉｆシディジタ
ルアナログ変、部器２８の出力信号１０２の値が１単位
博カロする。カウンタ２７はパルス電圧ＥＤの値が第１
の規定電圧Ｊｅ超えるまでカウントアツプされ続はパル
ス電圧ｇＤの値が４１の規定電圧Ｅ１と第２の規定電圧
Ｅ２の１−に入ったとき即ち光パルス強ハが蜆定値範ｐ
Ｈｖζ入つたときにカウントが行なイノ１′シなくなる
。, at time t1, when the generated pulse voltage ED is lower than the first specified +Lf, voltage E1, the counter 27 counts up by one if the output signal 102 of the digital/analog converter 28 is The value increases by 1 unit. The counter 27 has the first value of the pulse voltage ED.
The count is continued until the pulse voltage gD exceeds the specified voltage Je of 41, and when the value of the pulse voltage gD enters 1- of the specified voltage E1 of 41 and the second specified voltage E2, that is, the intensity of the light pulse reaches the specified value range p.
When Hvζ enters, a count is performed and the inoculation disappears.
一方、緒刻１４１こ、＃６けるようにパルス（圧Ｅ。の
値か第２の規定電圧Ｅ２を超えるとカウンタ２７（′ｆ
、カウントダウンされ１ｄ号１０２の値は１つ減少する
。On the other hand, when the value of the pulse (pressure E.
, and the value of No. 1d 102 decreases by one.
記４デークパルス１ｔｌｌの周期Ｔ８は橡めて短い時間
′ｔ″ありから１６号１０２の値の修正は＾速に行なわ
れる。また１回のパルス発生に対しＣは１単位しか修正
されないから外乱等により光パルスの強度が一時的に急
変しても信号１０２の値がそれに従って大きくずれる恐
れｌ′ｉ、ない。Since the period T8 of the 4th data pulse 1tll has an extremely short time ``t'', the value of No. 16 102 is corrected quickly.Also, since C is corrected by only 1 unit for one pulse generation, disturbances etc. Therefore, even if the intensity of the optical pulse suddenly changes temporarily, there is no possibility that the value of the signal 102 will vary greatly accordingly.
以上の如く本発明によれば間欠的に発生する元パルスの
強度が安定に制御さ−１１、温度変動等の外乱に抗して
一定強度の光パルスを発生することによって光学的記録
再生装置（ｆｃおける高品質な情報の６己録が可能とな
る。As described above, according to the present invention, the intensity of the original pulse that is generated intermittently is stably controlled, and the optical recording/reproducing apparatus ( It becomes possible to record high-quality information on fc.
なお、今迄の説明では説明の都合上半導体レーザを１史
用した場合の一部の例についてのみ示したが、電気光学
式光変調ｚ７ （ｎ −ｏ変調器）を吏用して光の変調
全行なう場合にも同様の方式が〕≦用できることは明ら
かであり本発明の範囲は上記の例に限定されるものでζ
・よない。In addition, in the explanation up to now, for convenience of explanation, we have shown only some examples where a semiconductor laser is used for one period, but it is possible to It is clear that a similar method can be used when all modulation is performed, and the scope of the present invention is limited to the above example.
・Yonai.
第１図は本発明の光量制御装置の一実施例金示すブロッ
ク図、第２図は４１図に示した装置の動作ヲ祝明するた
めの各部の１ｇ号波形の例を示す図である。
９−
図中、１０は半導体レーザ、１３は記録媒体、１４は光
咲出器、２０はバイアス電流供給回路、２１は変調駆動
回路、２３ ｖｉ第１の比較器、２４は第２の比較器、
２７．１カウンタ、２８ｖよディジ１０−FIG. 1 is a block diagram showing an embodiment of the light amount control device of the present invention, and FIG. 2 is a diagram showing an example of the No. 1g waveform of each part to explain the operation of the device shown in FIG. 41. 9- In the figure, 10 is a semiconductor laser, 13 is a recording medium, 14 is a light source, 20 is a bias current supply circuit, 21 is a modulation drive circuit, 23 vi first comparator, 24 is a second comparator ,
27.1 counter, 28v yo digi 10-
Claims (1)
体上に照射することにより情報の記録を行なう光学的記
録再生装置において、前記レーザ光源よりの光束の一部
を受けてレーザ光源の発光光量をモニターする光検出器
と、レーザ光パルス発生時に前記光検出器の出力が第一
の規定レベルを超えたことを検出する第一の比較器と、
削記元検出器の出力が、＠記第−の規定レベルより高い
第二の規定レベル奮起えたことを構出する第二の比較器
と、ｍ記し−ザ光パルス発生時に繭６ピ光検出器の出力
が前−第二の規定レベルを超えたときカウントダウンさ
れ上−光検出器の出力が上記第一の視だレベルに達しな
かったときカウントアツプきれるカウンタと、前記カウ
ンタの出力τディジタル・アナログ変換する変換器と″
ン備え、上記ディジタル・アナログ変換器の出力により
前記レーザ光の変調・彼を制御するよう゛でしたことを
特徴とする光学ＩＪｇ記録再生装置に３ける光量制御装
置。In an optical recording/reproducing device that records information by pulse-modulating the light flux from a laser light source and irradiating it onto an information recording medium, the amount of light emitted by the laser light source is determined by receiving a portion of the light flux from the laser light source. a first comparator that detects that the output of the photodetector exceeds a first specified level when a laser light pulse is generated;
A second comparator that detects that the output of the source detector has reached a second specified level higher than the specified level; a counter that counts down when the output of the photodetector exceeds the second predetermined level; and a counter that counts up when the output of the photodetector does not reach the first predetermined level; Analog converter and ″
3. A light amount control device for an optical IJG recording and reproducing device, characterized in that the laser beam is modulated and controlled by the output of the digital-to-analog converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56199830A JPS58100245A (en) | 1981-12-11 | 1981-12-11 | Controller for quantity of light of optical recording and reproducing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56199830A JPS58100245A (en) | 1981-12-11 | 1981-12-11 | Controller for quantity of light of optical recording and reproducing device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS58100245A true JPS58100245A (en) | 1983-06-14 |
Family
ID=16414345
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56199830A Pending JPS58100245A (en) | 1981-12-11 | 1981-12-11 | Controller for quantity of light of optical recording and reproducing device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58100245A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6132232A (en) * | 1984-07-25 | 1986-02-14 | Sony Corp | Control circuit for modulated laser beam |
| JPS6145727U (en) * | 1984-08-24 | 1986-03-26 | ソニー株式会社 | Control circuit for modulated laser light |
| US5231625A (en) * | 1990-09-27 | 1993-07-27 | International Business Machines Corporation | Optical disk drive wherein a preset reading laser power is used to generate a desired white laser power |
| US5493549A (en) * | 1990-04-10 | 1996-02-20 | Seiko Epson Corporation | Optical recording regeneration apparatus with compensation circuit |
| JP2001194242A (en) * | 1999-10-15 | 2001-07-19 | Hewlett Packard Co <Hp> | Multivalued optical pulse train analyzer/controller |
-
1981
- 1981-12-11 JP JP56199830A patent/JPS58100245A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6132232A (en) * | 1984-07-25 | 1986-02-14 | Sony Corp | Control circuit for modulated laser beam |
| JPS6145727U (en) * | 1984-08-24 | 1986-03-26 | ソニー株式会社 | Control circuit for modulated laser light |
| JPH0548257Y2 (en) * | 1984-08-24 | 1993-12-22 | ||
| US5493549A (en) * | 1990-04-10 | 1996-02-20 | Seiko Epson Corporation | Optical recording regeneration apparatus with compensation circuit |
| US5231625A (en) * | 1990-09-27 | 1993-07-27 | International Business Machines Corporation | Optical disk drive wherein a preset reading laser power is used to generate a desired white laser power |
| JP2001194242A (en) * | 1999-10-15 | 2001-07-19 | Hewlett Packard Co <Hp> | Multivalued optical pulse train analyzer/controller |
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