JPS6159639A - Method and device for controlling quantity of recording light - Google Patents

Method and device for controlling quantity of recording light

Info

Publication number
JPS6159639A
JPS6159639A JP59179296A JP17929684A JPS6159639A JP S6159639 A JPS6159639 A JP S6159639A JP 59179296 A JP59179296 A JP 59179296A JP 17929684 A JP17929684 A JP 17929684A JP S6159639 A JPS6159639 A JP S6159639A
Authority
JP
Japan
Prior art keywords
recording
signal
light
frequency
peak value
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
JP59179296A
Other languages
Japanese (ja)
Inventor
Koji Kamisaka
上坂　宏治
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.)
Victor Company of Japan Ltd
Original Assignee
Victor Company of Japan Ltd
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 Victor Company of Japan Ltd filed Critical Victor Company of Japan Ltd
Priority to JP59179296A priority Critical patent/JPS6159639A/en
Publication of JPS6159639A publication Critical patent/JPS6159639A/en
Pending legal-status Critical Current

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
    • 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
    • G11B7/004—Recording, reproducing or erasing methods; Read, write or erase circuits therefor
    • G11B7/0045—Recording

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  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Recording Or Reproduction (AREA)
  • Optical Head (AREA)

Abstract

PURPOSE:To record surely recording signals of high frequency and keep the quantity of light at an optimum value when the level and the duty ratio of recording signals are varied, by controlling variably the quantity of light in accordance with the peak value of the quantity of light of an optical beam or the frequency of recording signals. CONSTITUTION:A part of a laser beam of a laser generator 3 is supplied to a detector 4 for a recording signal (a), and the detection signal is supplied to an equalizer 5. The equalizer 5 generates an equalizing signal (b), whose amplitude is changed in accordance with the frequency, and supplies this signal to a peak detector 6, and the detector 6 detects the peak of the signal (b) and inverts it to generate a control signal (d) and supplies this signal (d) to a laser modulator 2. The modulator 2 superposes the signal (a) onto the signal (d) to generate a driving current (e) and supplies this current to the generator 3. Thus, the quantity of light of the laser light outputted from the generator 3 is increased in proportion to the current (e) according as the frequency is higher.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は記録光量制御方法及びその装置に係り、レーザ
光等の光を用いて記録媒体に情報の記録を行なう方式で
記録光量を最適なものに制りＩする記録光量制御方法及
びその装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method and apparatus for controlling the amount of recording light, which optimizes the amount of recording light by recording information on a recording medium using light such as a laser beam. The present invention relates to a recording light amount control method and apparatus thereof.

従来の技術 従来よりレーザ光等の光ビームを回転Ｊ゛る記録薄膜に
照射し、記録薄膜に例えばビットを形成して情報を記録
する情報記録方式がある。このような方式においては、
記録信号に応じてレーザ光発生器をオン・オフさせ記録
光を第６図（Ａ＞に示す如く断続させる第１の方式と、
所定のバイアス光示を設定して記録信号に応じて第６図
（Ｂ）に示す如く記録光を変化させる第２の方式とがあ
る。2. Description of the Related Art Conventionally, there is an information recording method in which a rotating recording thin film is irradiated with a light beam such as a laser beam to form, for example, bits on the recording thin film to record information. In such a method,
A first method in which a laser beam generator is turned on and off in accordance with a recording signal to intermittent recording light as shown in FIG. 6 (A>);
There is a second method in which a predetermined bias light intensity is set and the recording light is changed as shown in FIG. 6(B) according to the recording signal.

両方式ともレーザ光発生器の出力は第６図（Ａ）。The output of the laser light generator for both types is shown in Figure 6 (A).

（Ｂ）夫々に一点鎖線Ｉａ、Ｉｂで示す記録光量の平均
値が一定となるよう制御されてＪ５す、光量が破線［ａ
、［ｂ夫々に示づ°閾値を越えたとぎ信号が記録薄膜に
ビットとして記録される。(B) The average value of the recording light amount shown by the dashed-dotted lines Ia and Ib is controlled to be constant.
, [b, respectively, the signals exceeding the threshold values are recorded as bits on the recording thin film.

発明が解決しようとする問題点 ここで、記録信号の周波数は低域から高域まで広範囲で
ある。上記第１又は第２の方式では記録光量のピーク値
が略一定であるため、記録信号の周波数が犬なる場合、
記録光量が破線■ａ、［ｂ夫々の閾値を越える時間で短
かくなり記録薄膜に照射される絶対光量（光エネルギー
〉が不足して情報の記録が行なわれなくなる。Problems to be Solved by the Invention Here, the frequency of the recording signal is wide ranging from low to high frequencies. In the first or second method described above, since the peak value of the recording light amount is approximately constant, if the frequency of the recording signal is irregular,
The amount of recording light decreases in the time it takes to exceed the respective thresholds of broken lines (a) and [b, and the absolute amount of light (light energy) irradiated to the recording thin film becomes insufficient, and information is no longer recorded.

記録信号の周波数が大なる場合もこの記録を行なうため
には、例えば第６図（Ｃ）に示す如く記録信号の周波数
に応じ周波数が大なる程記録光量が増大するよう記録光
量の等化を行なうことが考えられる。In order to perform this recording even when the frequency of the recording signal becomes large, the amount of recording light must be equalized according to the frequency of the recording signal so that the amount of recording light increases as the frequency increases, as shown in FIG. 6(C). It is possible to do so.

しかし、従来装置では記録光量の平均ｆｉｎ（図中、一
点鎖線ＩＣで示す）が一定となるよう制御されるため、
実際の記録光量の最大値を知ることができない。従って
、記録信号がパルス波形の場合そのデユーティ比が変化
すると記録光量の最大値も変化してしまう。また、レー
ザ光発生器として半導体レーザを用いた場合、第３図の
実ＦＡｍａに示す如く記録信号電流が僅かに変動しただ
けでも記録光量は大きく橡化し、記録信号波形が歪んだ
どきには記録光■の最大値が最適な値とならず記録薄膜
に情報の記録が最適に行なえないという問題点があった
。However, in the conventional device, the average amount of recording light fin (indicated by the dashed line IC in the figure) is controlled to be constant.
It is not possible to know the maximum value of the actual recording light amount. Therefore, if the recording signal has a pulse waveform and its duty ratio changes, the maximum value of the recording light amount will also change. Furthermore, when a semiconductor laser is used as a laser beam generator, even a slight change in the recording signal current causes the recording light intensity to become large, as shown in the actual FAma in Figure 3, and when the recording signal waveform is distorted, the recording There was a problem in that the maximum value of the light (1) was not the optimum value and information could not be optimally recorded on the recording thin film.

そこで、本発明は先山のピーク値又はピーク値と記録信
号の周波数に応じて光ビームの光量を制御することによ
り、上記の問題点を解決した記録光１　ｆｉｉｌｌ　ｔ
ｉｔ方法及びその装置を提供することを目的とする。Therefore, the present invention solves the above problems by controlling the light intensity of the light beam according to the peak value of the first peak or the peak value and the frequency of the recording signal.
The purpose of the present invention is to provide an IT method and a device thereof.

問題点を解決するための手段 本発明において、光ビームよりその光量のピーク値は又
はピーク値及び記録信号の周波数が検出され、このピー
ク値又はピーク値及び周波数に応じて光ビームの光量が
制御される。Means for Solving the Problems In the present invention, the peak value of the light intensity of the light beam or the peak value and the frequency of the recording signal are detected, and the light intensity of the light beam is controlled according to the peak value or the frequency of the recorded signal. be done.

作用 本発明においては、記録媒体に照Ｑｌされる光ビームか
ら、その光量のピーク値又はピーク１直及び記録信号の
周波数を検出され、このピーク値又はピーク値及び周波
数に応じて光ビームの光（６）が制御される。これによ
って光ビームの光量は記録に最適な１直にｆｌｉｌＪ御
される。In the present invention, the peak value or peak value of the light quantity and the frequency of the recording signal are detected from the light beam shining on the recording medium, and the light of the light beam is adjusted according to the peak value or peak value and frequency. (6) is controlled. As a result, the light intensity of the light beam is controlled to the optimum level for recording.

実施例 第１図は本発明の一実施例のブロック系統図を示す。同
図中、端子１には例えばＦＭ信号等の記録信号ａが入来
づ゛る。この記録信号は第２図（Ａ）に示す如き波形の
ものであり、レーザ変調器２に供給される。レーザ変調
器２は後述するピーク検出器６よりの制御信号に応じた
値を基準として記録信号ａに対応した波形の駆動電流を
生成してレーザ発生器３に供給する。レーザ発生器３は
例えば駆動電流と発光量との関係が第３図の実線１１［
ａに示す如き特性を有する半導体レーザ素子である。Embodiment FIG. 1 shows a block system diagram of an embodiment of the present invention. In the figure, a recording signal a such as an FM signal, for example, is coming into terminal 1. This recording signal has a waveform as shown in FIG. 2(A), and is supplied to the laser modulator 2. The laser modulator 2 generates a drive current having a waveform corresponding to the recording signal a using a value corresponding to a control signal from a peak detector 6 as described later as a reference, and supplies it to the laser generator 3. For example, the relationship between the drive current and the amount of light emitted by the laser generator 3 is as shown by the solid line 11 in FIG.
This is a semiconductor laser device having characteristics as shown in a.

上記レーザ発生器３の出力レーザビームは光学系（図示
せず）を通って記録薄膜（記録媒体）に照ＩＪ’ｌされ
情報の記録を行なうと共に、その一部が検出器４に供給
される。The output laser beam of the laser generator 3 passes through an optical system (not shown) and is directed onto a recording thin film (recording medium) to record information, and a part of it is supplied to a detector 4. .

検出器４は例えば光ビームの光量と出力電流との関係が
第３図の実線Ｉｂに示す如くリニアであり高域まで周波
ｖｌｆｒ性の良いビンフォトダイオードである。検出器
４の光電変換により得られる検出信号は等止器５に供給
される。等化２（５は、例えば第４図の実線ＩＶに示Ｊ
−如く低域、中域、高域夫々の利得が異なる周波数特性
をイ、１してＪ５す、検出信号の低域及び中域のレベル
をＲＩＨｉのレベルに対して増強づ゛る。なＪ５、実線
［Ｖの特性は第４図の縦軸に記録薄膜の記録に必要な光
ｆｉ１をどったとぎの光ｎ・周波数特性の逆特性に対応
するものである。The detector 4 is, for example, a bin photodiode in which the relationship between the amount of light beam and the output current is linear as shown by the solid line Ib in FIG. 3, and has good frequency vlfr characteristics up to high frequencies. A detection signal obtained by photoelectric conversion of the detector 4 is supplied to an isolator 5 . Equalization 2 (5 is shown, for example, by the solid line IV in FIG.
- The frequency characteristics in which the gains of the low, middle, and high ranges are different are set to 1, and the levels of the low and middle ranges of the detection signal are enhanced relative to the level of RIHi. The characteristics of J5 and solid line [V correspond to the inverse characteristics of the light n/frequency characteristics when the light fi1 necessary for recording on the recording thin film is traced along the vertical axis in FIG.

ここで、当初ピーク検出器（３よりの制御信号がレーザ
変調器２に供給されないと仮定すると、第２図（Ａ＞の
記録信号ａに対してレーザ発生器３の発生するレーザビ
ームの光■及び検出器４の検出信号は略第２図（Ａ＞に
示す如き波形となり、等止器５は第２図（Ｂ）に示す如
く、周波数に応じて振幅が変化する等化信号すを生成し
てピーク検出器６に供給する。ピーク検出器６は等化信
号のピーク検波を行ない′５２図（Ｃ）に示ダ如ぎ信号
Ｃを得、更にこの信号Ｃを反転して第２図（Ｄ）に示ず
制ｉｋｌ信号ｄを生成しレーザ変調器２に供給ザる。Here, assuming that the control signal from the peak detector (3) is not initially supplied to the laser modulator 2, the light of the laser beam generated by the laser generator 3 in response to the recording signal a shown in FIG. The detection signal of the detector 4 has a waveform approximately as shown in FIG. 2 (A), and the equalizer 5 generates an equalized signal whose amplitude changes depending on the frequency, as shown in FIG. 2 (B). The peak detector 6 performs peak detection of the equalized signal to obtain a signal C as shown in FIG. A control ikl signal d is generated and supplied to the laser modulator 2, not shown in (D).

レーザ変調器２は制御信号ｄに記録信号ａを重畳して駆
動電流Ｏを生成する。これによって、レーザ変調器２の
出力する駆動電流ｅＩＪ第３図の実線ｌａのリニアな領
域内で記録信号ａの周波数に応じて第２図（Ｅ）に示す
如く変化する。従って、レーザ発生器３より出力される
レーザ光の光量は第２図（Ｅ）の駆動電流ｅに比例し、
周波数が高い程大となる。ここで第２図（Ｅ）に示す破
線■は、記録信号の各周波数において、記録薄膜に情報
の記録を行なうに必要な光量に応じた駆動電流の閾値を
表わしている。Laser modulator 2 generates drive current O by superimposing recording signal a on control signal d. As a result, the drive current eIJ output from the laser modulator 2 changes within the linear region indicated by the solid line la in FIG. 3 as shown in FIG. 2(E) according to the frequency of the recording signal a. Therefore, the amount of laser light output from the laser generator 3 is proportional to the drive current e in FIG. 2(E),
The higher the frequency, the larger it becomes. Here, the broken line (■) shown in FIG. 2(E) represents the threshold value of the drive current according to the amount of light necessary to record information on the recording thin film at each frequency of the recording signal.

このように、記録信号ａの周波数に応じて記録先車が変
化し、かつ、この記録光■の変化は記録薄膜の記録光帛
・周波数特性に対応したものであるから、記録薄膜には
周波数が大なる記録信号も確実に記録される。In this way, the recording destination wheel changes according to the frequency of the recording signal a, and the change in the recording light (2) corresponds to the recording optical fiber/frequency characteristics of the recording thin film. Even recording signals with large values can be reliably recorded.

また、レーザ変調器２はレーザ光の光量にピーク値が記
録信号ａの周波数に最適な値となるよう制御されるので
、記録信号ａのデユーティ比が変化しても記録光ｉｔは
常に最適な値となる。更に記録信号ａのレベルが変動し
た場合、例えば記録信号ａにハム雑音が混入して第２図
（Ｆ）に示す如くレベル変動がある場合も制御信号（１
は」上記レベル変動を打ら消υ゛向さ・に変動し、駆動
電流［３）、：Ｘ第２図（Ｇ）に示す如く一定レベルと
なり、記録光間のピーク値は一定な値に保持される。In addition, the laser modulator 2 is controlled so that the peak value of the laser beam intensity is the optimal value for the frequency of the recording signal a, so even if the duty ratio of the recording signal a changes, the recording light IT is always at the optimal value. value. Furthermore, when the level of the recording signal a fluctuates, for example, when hum noise is mixed into the recording signal a and the level fluctuates as shown in FIG. 2(F), the control signal (1
The drive current [3], :X becomes constant level as shown in Figure 2 (G), and the peak value between the recording beams becomes constant value. Retained.

ところで、記録信号ａの周波数変化が記録薄膜の記録光
量・周波数特性に影響のない程度で比較的少ない場合に
おいては、第１図示の等止器５の周波数特性を第４図の
破線Ｖｌに示す如く平坦にしても良い。この場合端子１
に第５図（Ａ）に示す如き振幅変動をもった記録信号が
入来しても、駆動電流ｅは第５図（８）に示す如くその
ピーク値が一定の値に保持され、記録光量のビーク直は
記録信号の周波数変化及び振幅変動に関係なく一定とな
る。また、この場合も記録信号ａが第２図（Ｆ）に示す
如（ハム雑音を含んでいても、駆動電流ｅは第２図（Ｇ
）に示す如くそのピーク値が一定に制御されることはも
ちろんである。By the way, when the frequency change of the recording signal a is relatively small and does not affect the recording light amount/frequency characteristics of the recording thin film, the frequency characteristics of the equalizer 5 shown in FIG. 1 are shown by the broken line Vl in FIG. 4. It may be made flat like this. In this case terminal 1
Even if a recording signal with amplitude fluctuations as shown in FIG. 5(A) is received, the peak value of the drive current e is maintained at a constant value as shown in FIG. 5(8), and the recording light amount is The peak directivity of is constant regardless of frequency changes and amplitude fluctuations of the recording signal. In this case as well, even if the recording signal a contains hum noise as shown in FIG. 2(F), the drive current e is
), the peak value is of course controlled to be constant.

なお、等止器５の利得・周波数特性は使用される記録薄
膜の記録光■・周波数特性の逆特性に対応するものであ
るが、等止器の利得・周波数特性を記録薄膜の記録周波
数特性に対応するものとし、ピーク検出器６でピーク検
波して得られる信号を反転づることなくそのまま制御信
号としてレーザ変調器２に供給するよう溝底しても良く
、上記実施例に限定されない。The gain and frequency characteristics of the equalizer 5 correspond to the inverse characteristics of the recording light and frequency characteristics of the recording thin film used, but the gain and frequency characteristics of the equalizer 5 correspond to the recording frequency characteristics of the recording thin film. The present invention is not limited to the above embodiment, and the groove bottom may be configured so that the signal obtained by peak detection by the peak detector 6 is supplied as a control signal to the laser modulator 2 without being inverted.

発明の効果 上ｊホの如く、本発明になる記録光量制御方法は、光ビ
ームの光量のピーク値又はピーク値及び記録信号の周波
数に応じて上記光ビームの光量を可変制御するため、記
録信号の周波数が大なる場合もこの記録ｆＣ号を確実に
記録でき、また記録信号のレベル変動及びデユーティ比
の変動がある場合にも光ビームの光量は記録にＲ適な１
ｒａに保持される等の特長を有している。In terms of effects of the invention, the recording light amount control method according to the present invention variably controls the light amount of the light beam according to the peak value of the light amount of the light beam or the peak value and the frequency of the recording signal. Even when the frequency of the recording fC is large, this recording fC number can be reliably recorded, and even when there are fluctuations in the level of the recording signal and fluctuations in the duty ratio, the light intensity of the light beam can be set to R1 suitable for recording.
It has features such as being held in ra.

また本発明装置は、上記の方法を実現可能なものとする
等の特長を有している。Furthermore, the device of the present invention has features such as making the above method possible.

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

第１図は本発明の一実施例のブロック系統図、第２図、
第５図は第１図示の各回路の信号波形図、第３図、第４
図は第１図示の一部回路の特性を示す図、第６図は従来
方式を説明するための図である。 ２・・・レーザ変調器、３・・・レーザ発生器、４・・
・検出器、５・・・等化器、６・・・ピーク検出器。 特許出願人　日本ビクター株式会社 第１図 第３図 第２図 第４図 一一一→ｉ司淑〕（ 第５図 第６図 （Ａ）　　　　　　　　　（Ｂ） （Ｃ） η′開FIG. 1 is a block system diagram of an embodiment of the present invention, FIG.
Figure 5 is a signal waveform diagram of each circuit shown in Figure 1, Figures 3 and 4.
The figure is a diagram showing the characteristics of a part of the circuit shown in Figure 1, and Figure 6 is a diagram for explaining the conventional system. 2... Laser modulator, 3... Laser generator, 4...
- Detector, 5... Equalizer, 6... Peak detector. Patent applicant Victor Company of Japan Co., Ltd. Figure 1 Figure 3 Figure 2 Figure 4

Claims (2)

【特許請求の範囲】[Claims] （１）記録信号で変調された光ビームを記録媒体に照射
して該記録媒体に情報を記録する光情報記録方式の記録
光量制御方法において、該記録媒体に照射される光ビー
ムより光量のピーク値又は該ピーク値及び該記録信号の
周波数を検出し、該ピーク値又は該ピーク値及び該周波
数に応じて該光ビームの光量を可変制御することを特徴
とする記録光量制御方法。(1) In a recording light amount control method of an optical information recording method in which a light beam modulated by a recording signal is irradiated onto a recording medium to record information on the recording medium, the light amount peaks from the light beam irradiated onto the recording medium. A recording light amount control method, comprising: detecting a value or a peak value and a frequency of the recording signal, and variably controlling the light amount of the light beam according to the peak value or the peak value and the frequency. （２）記録信号で変調された光ビームを記録媒体に照射
して該記録媒体に情報を記録する光情報記録方式の記録
光量制御装置において、該記録媒体に照射される光ビー
ムより記録光量のピーク値又は該ピーク値及び該記録信
号の周波数を検出する検出回路と、該ピーク値又は該ピ
ーク値及び該周波数に応じて該光ビームの光量を可変制
御する制御回路とより構成したことを特徴とする記録光
量制御装置。(2) In a recording light amount control device using an optical information recording method that records information on a recording medium by irradiating a light beam modulated with a recording signal onto the recording medium, the recording light amount is smaller than the light beam irradiated onto the recording medium. It is characterized by being comprised of a detection circuit that detects a peak value or the peak value and the frequency of the recording signal, and a control circuit that variably controls the light amount of the light beam according to the peak value or the peak value and the frequency. Recording light amount control device.
JP59179296A 1984-08-30 1984-08-30 Method and device for controlling quantity of recording light Pending JPS6159639A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59179296A JPS6159639A (en) 1984-08-30 1984-08-30 Method and device for controlling quantity of recording light

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59179296A JPS6159639A (en) 1984-08-30 1984-08-30 Method and device for controlling quantity of recording light

Publications (1)

Publication Number Publication Date
JPS6159639A true JPS6159639A (en) 1986-03-27

Family

ID=16063344

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59179296A Pending JPS6159639A (en) 1984-08-30 1984-08-30 Method and device for controlling quantity of recording light

Country Status (1)

Country Link
JP (1) JPS6159639A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02137133A (en) * 1988-11-17 1990-05-25 Nec Corp Optical recording and reproducing device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02137133A (en) * 1988-11-17 1990-05-25 Nec Corp Optical recording and reproducing device

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