JPH1139739A - Reproducing light quantity control device in optical storage device and optical recording medium - Google Patents
Reproducing light quantity control device in optical storage device and optical recording mediumInfo
- Publication number
- JPH1139739A JPH1139739A JP9192361A JP19236197A JPH1139739A JP H1139739 A JPH1139739 A JP H1139739A JP 9192361 A JP9192361 A JP 9192361A JP 19236197 A JP19236197 A JP 19236197A JP H1139739 A JPH1139739 A JP H1139739A
- Authority
- JP
- Japan
- Prior art keywords
- mark
- reproduction
- reproducing
- power control
- recording medium
- 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.)
- Granted
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
- G11B7/1267—Power calibration
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/10009—Improvement or modification of read or write signals
- G11B20/10037—A/D conversion, D/A conversion, sampling, slicing and digital quantisation or adjusting parameters thereof
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/10009—Improvement or modification of read or write signals
- G11B20/10268—Improvement or modification of read or write signals bit detection or demodulation methods
- G11B20/10277—Improvement or modification of read or write signals bit detection or demodulation methods the demodulation process being specifically adapted to partial response channels, e.g. PRML decoding
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
- G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
- G11B27/19—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
- G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
- G11B27/19—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier
- G11B27/28—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier by using information signals recorded by the same method as the main recording
- G11B27/30—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier by using information signals recorded by the same method as the main recording on the same track as the main recording
- G11B27/3027—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier by using information signals recorded by the same method as the main recording on the same track as the main recording used signal is digitally coded
-
- 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
- G11B7/007—Arrangement of the information on the record carrier, e.g. form of tracks, actual track shape, e.g. wobbled, or cross-section, e.g. v-shaped; Sequential information structures, e.g. sectoring or header formats within a track
- G11B7/00745—Sectoring or header formats within a track
-
- 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
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/2403—Layers; Shape, structure or physical properties thereof
- G11B7/24035—Recording layers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B2220/00—Record carriers by type
- G11B2220/20—Disc-shaped record carriers
- G11B2220/25—Disc-shaped record carriers characterised in that the disc is based on a specific recording technology
- G11B2220/2537—Optical discs
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Optical Recording Or Reproduction (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、磁気的超解像方式
の光記録媒体に光ビームを照射し、記録マークからの再
生信号が所定の値に近づくように光ビームの光量を制御
する光記憶装置における再生光量制御装置及び光記録媒
体に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source for irradiating an optical recording medium of a magnetic super-resolution type with a light beam and controlling the light amount of the light beam so that a reproduction signal from a recording mark approaches a predetermined value. The present invention relates to a reproduction light amount control device and an optical recording medium in a storage device.
【0002】[0002]
【従来の技術】光磁気ディスク装置において、記録層と
面内磁化を有する再生層とを備えた磁気的超解像方式の
光磁気ディスクに対して、再生層側から光ビームを照射
して、照射領域内で所定の温度以上に温度が上昇した部
分(以下、アパーチャという)のみの再生層が、対応す
る記録層の磁性が転写されて面内磁化から垂直磁化に移
行することにより、光ビームのスポット径よりも小さい
記録マークの再生を可能にしている。2. Description of the Related Art In a magneto-optical disk drive, a magneto-optical disk of a magnetic super-resolution type having a recording layer and a reproducing layer having in-plane magnetization is irradiated with a light beam from the reproducing layer side. The reproducing layer only in a portion (hereinafter, referred to as an aperture) whose temperature has risen to a predetermined temperature or higher in the irradiation area transfers the magnetization of the corresponding recording layer and shifts from in-plane magnetization to perpendicular magnetization, so that the light beam It is possible to reproduce a recording mark smaller than the spot diameter.
【0003】この方式においては、光ビームを発生させ
る駆動電流を一定に保っていても、再生時の環境温度の
変化に応じて光ビームの再生パワーが変動してしまうこ
とがある。そして、再生パワーが強くなり過ぎるとアパ
ーチャが大きくなり過ぎて、隣接するトラックからの再
生信号の出力が増大し、再生されるデータに含まれる雑
音信号の割合が多くなって、読み取りエラーの発生する
確率が高くなる。また、再生パワーが弱くなり過ぎる
と、記録マークよりもアパーチャが小さくなるととも
に、読み取ろうとしているトラックからの再生信号の出
力も小さくなって、やはり読み取りエラーの発生確率が
高くなる。In this method, even if the driving current for generating the light beam is kept constant, the reproduction power of the light beam may fluctuate in accordance with the change in the environmental temperature during reproduction. If the reproduction power becomes too strong, the aperture becomes too large, the output of the reproduction signal from the adjacent track increases, and the ratio of the noise signal included in the reproduced data increases, causing a reading error. The probability increases. On the other hand, if the reproduction power becomes too weak, the aperture becomes smaller than that of the recording mark, and the output of the reproduction signal from the track to be read becomes smaller, which also increases the probability of occurrence of a read error.
【0004】そこで、特開平8−63817号公報で
は、光磁気ディスク上の異なる2種類の長さの再生パワ
ー制御用マークを再生し、それらの再生信号の比が所定
値に近づくように再生パワーを制御することによって、
再生パワーを常に最適値に保持し、読み取りエラーの発
生する確率を減少させている。図12に、この装置の大
まかな構成を示す。半導体レーザ2からの出射光が光磁
気ディスク12に照射されると、光磁気ディスク12上
の再生パワー制御用マークからの反射光がフォトダイオ
ード3によって再生信号に変換される。再生信号はA/
D(Analog/Digital)変換器5とクロッ
ク生成回路4に入力される。クロック生成回路4は、P
LL(Phase Locked Loop)によって
再生信号に同期したクロック信号を生成する。そして、
A/D変換器5において、このクロック信号に基づいて
再生信号がデジタルデータに変換される。振幅比検出回
路13は、クロック信号毎に入力されるデジタルデータ
のうち、上下ピーク点のデジタルデータのみを取り出し
て、所定サンプル数で平均化することによって、振幅値
の平均値を検出する。このように長マークと短マークの
平均振幅値を検出して、これらの比を求めて平均振幅比
として出力する。差動増幅器10はこの平均振幅比と目
標値を比較し、その差が小さくなる方向にフィードバッ
クがかかるように、再生パワー制御回路11が半導体レ
ーザ2への駆動電流を制御する。このようにして、常に
最適な再生パワーが与えられるようにレーザ光の駆動電
流が制御される。Japanese Patent Laid-Open Publication No. Hei 8-63817 discloses reproducing power control marks of two different lengths on a magneto-optical disk and reproducing power control marks such that the ratio of the reproduced signals approaches a predetermined value. By controlling
The reproduction power is always kept at an optimum value, and the probability of occurrence of a reading error is reduced. FIG. 12 shows a schematic configuration of this device. When the light emitted from the semiconductor laser 2 is applied to the magneto-optical disk 12, the reflected light from the reproduction power control mark on the magneto-optical disk 12 is converted into a reproduction signal by the photodiode 3. The playback signal is A /
It is input to a D (Analog / Digital) converter 5 and a clock generation circuit 4. The clock generation circuit 4
A clock signal synchronized with the reproduction signal is generated by LL (Phase Locked Loop). And
In the A / D converter 5, the reproduced signal is converted into digital data based on the clock signal. The amplitude ratio detection circuit 13 detects only the digital data at the upper and lower peak points from the digital data input for each clock signal, and averages the digital data at a predetermined number of samples, thereby detecting the average value of the amplitude values. As described above, the average amplitude values of the long mark and the short mark are detected, the ratio between them is obtained, and the ratio is output as the average amplitude ratio. The differential amplifier 10 compares the average amplitude ratio with the target value, and the reproduction power control circuit 11 controls the drive current to the semiconductor laser 2 so that feedback is applied in a direction in which the difference becomes smaller. In this way, the drive current of the laser light is controlled so that the optimum reproduction power is always provided.
【0005】[0005]
【発明が解決しようとする課題】しかしながら、振幅比
の平均値を求めるために用いるサンプル数が多すぎる
と、光記録媒体における再生パワー制御用マークの記録
領域の占める割合が大きくなりすぎて、光記録媒体の利
用効率が悪化してしまう。又、サンプル数が少なすぎる
と、検出される振幅比のばらつきが大きくなり、再生パ
ワーの制御誤差が大きくなってしまう。However, if the number of samples used for obtaining the average value of the amplitude ratio is too large, the ratio of the recording area of the reproduction power control mark in the optical recording medium becomes too large, and The use efficiency of the recording medium is deteriorated. On the other hand, if the number of samples is too small, the variation in the detected amplitude ratio increases, and the control error of the reproduction power increases.
【0006】本発明は、再生パワー制御のための振幅比
の平均化に用いるピーク値のサンプル数を最適な範囲に
設定することによって、求められる平均振幅比のばらつ
きを小さくして再生パワーの制御誤差を小さく抑えると
ともに、再生パワー制御用マークの記録領域を小さくし
て、光記録媒体の利用効率を向上させることを目的とす
る。According to the present invention, reproduction power control is performed by setting the number of peak value samples used for averaging the amplitude ratio for reproduction power control in an optimum range, thereby reducing variations in the average amplitude ratio obtained. It is an object of the present invention to reduce the error and to reduce the recording area of the reproduction power control mark to improve the use efficiency of the optical recording medium.
【0007】[0007]
【課題を解決するための手段】請求項1に記載の光記憶
装置における再生光量制御装置は、照射された光ビーム
の光スポット径よりも小さなアパーチャを再生層に発生
させることにより記録層からの記録情報を再生する光記
録媒体を用い、該光記録媒体に記録された再生パワー制
御用マークからの再生信号を検出して再生パワーを制御
する制御手段を有する光記憶装置における再生光量制御
装置において、前記制御手段は、前記再生パワー制御用
マークを5バイト以上40バイト以下の範囲で再生して
得られる再生信号に基づいて再生パワーを制御すること
を特徴とする。According to a first aspect of the present invention, there is provided a reproduction light amount control device for an optical storage device, wherein an aperture smaller than a light spot diameter of an irradiated light beam is generated in a reproduction layer to thereby generate a light from a recording layer. A reproduction light amount control device in an optical storage device using an optical recording medium for reproducing recorded information and having control means for controlling a reproduction power by detecting a reproduction signal from a reproduction power control mark recorded on the optical recording medium. The control means controls the reproduction power based on a reproduction signal obtained by reproducing the reproduction power control mark in a range of 5 bytes or more and 40 bytes or less.
【0008】請求項2に記載の光記憶装置における再生
光量制御装置は、照射された光ビームの光スポット径よ
りも小さなアパーチャを再生層に発生させることにより
記録層からの記録情報を再生する光記録媒体を用い、該
光記録媒体に記録された再生パワー制御用マークからの
再生信号を検出して再生パワーを制御する制御手段を有
する光記憶装置における再生光量制御装置において、前
記制御手段は、前記再生パワー制御用マークを(40/
3)サンプル以上120サンプル以下の範囲で再生して
得られる再生信号に基づいて再生パワーを制御すること
を特徴とする。According to a second aspect of the present invention, there is provided a reproducing light amount control device for an optical storage device, wherein an aperture smaller than a light spot diameter of an irradiated light beam is generated in a reproducing layer to reproduce recorded information from the recording layer. Using a recording medium, in a reproduction light amount control device in an optical storage device having a control unit that controls a reproduction power by detecting a reproduction signal from a reproduction power control mark recorded on the optical recording medium, the control unit includes: The reproduction power control mark is set to (40 /
3) The reproduction power is controlled based on a reproduction signal obtained by reproducing in a range of not less than samples and not more than 120 samples.
【0009】請求項3に記載の光記憶装置における再生
光量制御装置は、請求項1または請求項2に記載の光記
憶装置における再生光量制御装置において、前記再生信
号をA/D変換して得られた複数の振幅値を平均化する
平均化手段を備えることを特徴とする。According to a third aspect of the present invention, there is provided a reproduction light amount control device for an optical storage device, wherein the reproduction signal is A / D converted. Averaging means for averaging a plurality of obtained amplitude values.
【0010】請求項4に記載の光記録媒体は、照射され
た光ビームの光スポット径よりも小さなアパーチャを再
生層に発生させることにより記録層からの記録情報を再
生する光記録媒体において、5バイト以上40バイト以
下の再生パワー制御用マークが記録されていることを特
徴とする。According to a fourth aspect of the present invention, there is provided an optical recording medium for reproducing recorded information from a recording layer by generating an aperture in the reproducing layer smaller than the light spot diameter of the irradiated light beam. It is characterized in that a reproduction power control mark of not less than bytes and not more than 40 bytes is recorded.
【0011】請求項5に記載の光記録媒体は、請求項4
に記載の光記録媒体において、前記再生パワー制御用マ
ークは、短マークの繰り返しパターンと長マークの繰り
返しパターンとからなり、各繰り返しパターンは5バイ
ト以上40バイト以下であることを特徴とする。The optical recording medium according to the fifth aspect is the fourth aspect of the invention.
Wherein the read power control mark is composed of a short mark repetition pattern and a long mark repetition pattern, and each repetition pattern is 5 bytes or more and 40 bytes or less.
【0012】請求項6に記載の光記録媒体は、請求項4
に記載の光記録媒体において、前記再生パワー制御用マ
ークは、セクタ毎に設けられていることを特徴とする。The optical recording medium according to the sixth aspect is the fourth aspect.
3. The optical recording medium according to claim 1, wherein the reproduction power control mark is provided for each sector.
【0013】[0013]
【発明の実施の形態】本発明の実施の形態について図を
用いて説明する。図1に、超解像光磁気ディスク再生装
置に本発明を適用した場合の実施の形態を示す。ただ
し、図12に示した従来装置と同様の機能を有する部分
については、同一番号を付して説明を省略する。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied to a super-resolution magneto-optical disk reproducing apparatus. However, portions having the same functions as those of the conventional device shown in FIG.
【0014】図2に、光磁気ディスク1のセクタ構造を
模式的に示す。図3に、短マークと長マークとからなる
再生パワー制御用マークを示す。図2において、セクタ
100は、短マークとして2Tc(Tcはチャネルビッ
ト長)の繰り返しパターン(図3(a)に示す)をKバ
イト記録した短マーク記録領域101、長マークとして
8Tcの繰り返しパターン(図3(b)に示す)を同じ
くKバイト記録した長マーク記録領域102、(1,
7)RLL変調されたデジタルデータを記録するデータ
記録領域103からなっている。FIG. 2 schematically shows the sector structure of the magneto-optical disk 1. FIG. 3 shows a reproduction power control mark composed of a short mark and a long mark. In FIG. 2, a sector 100 has a short mark recording area 101 in which a repetition pattern (shown in FIG. 3A) of 2Tc (Tc is a channel bit length) as a short mark is recorded in K bytes, and a repetition pattern of 8Tc as a long mark ( FIG. 3B) also shows a long mark recording area 102 in which K bytes are recorded.
7) It has a data recording area 103 for recording RLL-modulated digital data.
【0015】図1において、この再生装置は、従来装置
と比較して、上記のような構造のセクタを複数含む光磁
気ディスク1、短マークの繰り返しパターンの平均振幅
値を検出する短マークレベル検出回路6、長マークの繰
り返しパターンの平均振幅値を検出する長マークレベル
検出回路7、データ記録領域103に記録されたデジタ
ルデータを再生するデータ再生回路8、短マークレベル
検出回路6の出力と長マークレベル検出回路7の出力を
割り算して平均振幅比を出力する割算器9の構成が相違
している。In FIG. 1, this reproducing apparatus is different from the conventional apparatus in that the magneto-optical disk 1 includes a plurality of sectors having the above-described structure, and a short mark level detecting means for detecting an average amplitude value of a repetitive pattern of short marks. A circuit 6, a long mark level detection circuit 7 for detecting an average amplitude value of a repeated pattern of a long mark, a data reproduction circuit 8 for reproducing digital data recorded in the data recording area 103, and an output and a length of the short mark level detection circuit 6. The configuration of a divider 9 that divides the output of the mark level detection circuit 7 and outputs the average amplitude ratio is different.
【0016】半導体レーザ2からの出射光は、光磁気デ
ィスク1上のセクタ100にアクセスするとまず最初に
短マーク記録領域101に照射される。短マーク記録領
域101からの反射光はフォトダイオード3によって再
生信号に変換される。再生信号はクロック生成回路4に
入力されて、再生信号のチャネルビット周波数に同期し
たクロック信号が生成、出力される。A/D変換器5
は、クロック生成回路4から出力されるクロック信号の
タイミングに基づいて再生信号をデジタル信号に変換し
て、短マークレベル検出回路6に出力する。短マークレ
ベル検出回路6は、短マーク記録領域101の再生を終
えるまですべての入力デジタル信号を保持し続け、再生
が終わった時点で保持したデジタル信号の上下ピークサ
ンプリング点のみを抽出して平均化処理し、短マーク振
幅値として出力する。次に半導体レーザ2からの出射光
は長マーク記録領域102に照射され、短マークの場合
と同様の処理が行われて、長マークレベル検出回路7か
ら長マーク振幅値が出力される。割算器9は入力された
短マーク振幅値と長マーク振幅値の比を計算して平均振
幅比として出力する。出力された平均振幅比は差動増幅
器10にて目標値と比較され、その差が小さくなる方向
にフィードバックがかかるように、再生パワー制御回路
11が半導体レーザ2への駆動電流を制御する。このよ
うにして、最適な再生パワーが与えられるようにレーザ
光の駆動電流が制御された後、出射光はデータ記録領域
103に照射され、読み出された再生信号がA/D変換
器5を経てデータ再生回路8に入力されて、エラーレー
トの低い二値化データが出力される。そして、出射光が
次のセクタに到達すると、同様の処理が繰り返されて、
新たに最適な再生パワーが設定し直される。このよう
に、再生パワー制御用マークの記録領域をセクタ毎に分
散して設けて、セクタ毎に再生パワー制御のための再生
信号量を検出することにより、短い時間間隔で再生パワ
ー制御が応答し、最適再生パワーの短時間の変動に追従
することが可能となる。When the light emitted from the semiconductor laser 2 accesses the sector 100 on the magneto-optical disk 1, the short mark recording area 101 is first irradiated. Light reflected from the short mark recording area 101 is converted into a reproduction signal by the photodiode 3. The reproduction signal is input to the clock generation circuit 4, and a clock signal synchronized with the channel bit frequency of the reproduction signal is generated and output. A / D converter 5
Converts the reproduction signal into a digital signal based on the timing of the clock signal output from the clock generation circuit 4 and outputs the digital signal to the short mark level detection circuit 6. The short mark level detection circuit 6 keeps holding all the input digital signals until the reproduction of the short mark recording area 101 is finished, and extracts and averages only the upper and lower peak sampling points of the held digital signal when the reproduction is finished. Process and output as a short mark amplitude value. Next, the light emitted from the semiconductor laser 2 is applied to the long mark recording area 102, the same processing as that for the short mark is performed, and the long mark level detection circuit 7 outputs the long mark amplitude value. The divider 9 calculates the ratio between the input short mark amplitude value and long mark amplitude value and outputs the result as an average amplitude ratio. The output average amplitude ratio is compared with a target value by the differential amplifier 10, and the reproduction power control circuit 11 controls the drive current to the semiconductor laser 2 so that feedback is applied in a direction in which the difference is reduced. After the driving current of the laser beam is controlled so that the optimum reproducing power is given in this way, the emitted light is irradiated to the data recording area 103, and the read reproduction signal is transmitted to the A / D converter 5. After that, the binary data is input to the data reproducing circuit 8 and output at a low error rate. Then, when the outgoing light reaches the next sector, the same processing is repeated,
The optimum reproduction power is newly set. As described above, the recording area of the reproduction power control mark is provided separately for each sector, and the reproduction signal control for the reproduction power control is detected for each sector, whereby the reproduction power control responds at a short time interval. Thus, it is possible to follow a short-term fluctuation of the optimum reproducing power.
【0017】ここで、短マークレベル検出回路6におけ
る短マーク振幅値の検出処理を図4(a)、図5を用い
て詳細に説明する。図4(a)は短マークの繰り返しパ
ターンの再生信号におけるA/D変換サンプリング点を
示す模式図である。クロック信号によって、上側ピーク
点(ds4i)、中間点(ds4i+1)、下側ピーク点(d
s4i+2)、中間点(ds4i+3)、の順でサンプリングさ
れる。Here, the detection processing of the short mark amplitude value in the short mark level detection circuit 6 will be described in detail with reference to FIGS. FIG. 4A is a schematic diagram showing A / D conversion sampling points in a reproduction signal of a repeated pattern of short marks. The upper peak point (ds 4i ), the middle point (ds 4i + 1 ), and the lower peak point (d
s 4i + 2 ) and the intermediate point (ds 4i + 3 ).
【0018】図5は短マークレベル検出回路6の詳細構
成を示している。クロック毎に入力される短マークのデ
ジタル再生信号は4N段シフトレジスタ61に順に記憶
されていく。短マークの上側ピーク点は4サンプリング
点毎に入力されるので、図のように4サンプリング点毎
のデジタル値(ds0、ds4、・・・、ds4(N-1))を
加算器62で加算し、割算器64にてNで割った値が上
側ピーク点の平均値Tsmeanとなる。同様に、4サンプ
リング点毎の下側サンプリング点のデジタル値(d
s2、ds6、・・・、ds4(N-1)+2)を加算器63で加
算して、割算器65にてNで割った値が下側ピーク点の
平均値Bsmeanとなる。減算器66にて求めたこれらの
差(Tsmean−Bsmean)が短マークの平均振幅値とし
て出力される。FIG. 5 shows a detailed configuration of the short mark level detection circuit 6. The digital reproduction signal of the short mark input for each clock is sequentially stored in the 4N-stage shift register 61. Since the upper peak point of the short mark is input at every four sampling points, the digital values (ds 0 , ds 4 ,..., Ds 4 (N−1) ) at every four sampling points are added as shown in the figure. The value added at 62 and divided by N at the divider 64 becomes the average value Ts mean of the upper peak points. Similarly, the digital value of the lower sampling point (d
s 2 , ds 6 ,..., ds 4 (N−1) +2 ) are added by the adder 63, and a value obtained by dividing by N in the divider 65 is the average value Bs mean of the lower peak point. Becomes The difference (Ts mean -Bs mean ) obtained by the subtractor 66 is output as the average amplitude value of the short mark.
【0019】次に、長マークレベル検出回路7における
長マーク振幅値の検出処理を図4(b)、図6を用いて
詳細に説明する。図4(b)は長マークの繰り返しパタ
ーンの再生信号におけるA/D変換サンプリング点を示
す模式図である。クロック信号によって、上側エンベロ
ープ点4点(dl16i、dl16i+1、dl16i+2、dl
16i+3)、中間点4点(dl16i+4、dl16i+5、dl
16i+6、dl16i+7)、下側エンベロープ点4点(dl
16i+8、dl16i+9、dl16i+10、dl16i+11)、中間点
4点(dl16i+12、dl16i+13、dl16i+14、dl
16i+15)の順でサンプリングされる。Next, the detection processing of the long mark amplitude value in the long mark level detection circuit 7 will be described in detail with reference to FIGS. FIG. 4B is a schematic diagram showing A / D conversion sampling points in a reproduction signal of a long mark repeating pattern. According to the clock signal, four upper envelope points (dl 16i , dl 16i + 1 , dl 16i + 2 , dl
16i + 3 ), 4 intermediate points (dl 16i + 4 , dl 16i + 5 , dl
16i + 6 , dl 16i + 7 ), 4 lower envelope points (dl
16i + 8 , dl 16i + 9 , dl 16i + 10 , dl 16i + 11 ), 4 intermediate points (dl 16i + 12 , dl 16i + 13 , dl 16i + 14 , dl
16i + 15 ).
【0020】図6は長マークレベル検出回路7の詳細構
成を示している。クロック毎に入力される長マークのデ
ジタル信号は16M段シフトレジスタ71に順に記憶さ
れていく。長マークの上側エンベロープ点は16サンプ
リング点毎に4サンプリング点が入力されるので、16
サンプリング点毎に4サンプリング点のデジタル値(d
l0、dl1、dl2、dl3、・・・、dl16(M-1)、d
l16(M-1)+1、dl16(M -1)+2、dl16(M-1)+3)を加算
器72で加算し、割算器74にて4Mで割った値が上側
ピーク点の平均値Tlmeanとなる。同様に、16サンプ
リング点毎に4サンプリング点の下側エンベロープ点の
デジタル値(dl8、dl9、dl10、dl11、・・・、
dl16(M-1)+8、dl16(M-1)+9、dl16(M-1)+10、dl
16(M-1)+11)を加算器73で加算して、割算器75にて
4Mで割った値が下側エンベロープ点の平均値Blmean
となる。減算器76にて求めたこれらの差(Tlmean−
Blmean)が長マークの平均振幅値として出力される。FIG. 6 shows a detailed configuration of the long mark level detection circuit 7. The digital signal of the long mark input for each clock is sequentially stored in the 16M-stage shift register 71. As the upper envelope point of the long mark is input at 4 sampling points every 16 sampling points, 16
The digital value of four sampling points (d
l 0, dl 1, dl 2 , dl 3, ···, dl 16 (M-1), d
l 16 (M-1) +1 , dl 16 (M -1) +2 , dl 16 (M-1) +3 ) are added by an adder 72, and a value obtained by dividing by 4M by a divider 74 is It becomes the average value Tl mean of the upper peak point. Similarly, every 16 sampling points, the digital value (dl 8 , dl 9 , dl 10 , dl 11 ,.
dl16 (M-1) +8 , dl16 (M-1) +9 , dl16 (M-1) +10 , dl
16 (M-1) +11 ) is added by an adder 73, and a value obtained by dividing by 4M by a divider 75 is an average value Bl mean of the lower envelope point.
Becomes These differences (Tl mean −
Bl mean ) is output as the average amplitude value of the long mark.
【0021】このようにして検出される振幅比(Ts
mean−Bsmean)/(Tlmean−Blmean)の精度は、
制御に用いる再生パワー制御用マークの平均化バイト数
Kによって変化する。図7に、磁気的超解像光磁気ディ
スク再生装置にて、平均化バイト数Kと検出された振幅
比の精度(100回分の検出結果の分布の標準偏差で表
す。標準偏差が小さい程ばらつきが小さい)の関係を実
測した結果を示す。図7より、平均化バイト数Kが40
バイト以上になると、標準偏差はほとんど変化していな
いことが分かる。よって、平均化バイト数は40バイト
以下にすれば十分である。The amplitude ratio (Ts) thus detected
The accuracy of mean− Bs mean ) / (Tl mean −Bl mean ) is
It changes depending on the averaged byte number K of the reproduction power control mark used for control. FIG. 7 shows the average number of bytes K and the accuracy of the detected amplitude ratio (represented by the standard deviation of the distribution of the detection results for 100 times. The smaller the standard deviation, the smaller the variation. 3) shows the results of the actual measurement of the relationship (1). According to FIG. 7, the averaged byte number K is 40
It can be seen that the standard deviation hardly changes when the size exceeds bytes. Therefore, it is sufficient that the number of averaged bytes is 40 bytes or less.
【0022】一方、再生装置で用いられるエラー訂正処
理回路の訂正能力から考えて、通常、ビットエラーレー
トは1E−4(=1×10-4)以下であればよいとされ
ている。図8に、図7と同じ再生装置にて、半導体レー
ザの再生パワーと再生された二値化データのビットエラ
ーレート(BER)及び長短マークの振幅比との関係を
実測した結果を示す。図8の測定結果で見ると、振幅比
が0.14から0.28の範囲、すなわち0.21±
0.07となる再生パワーにて、ビットエラーレートが
1E−4以下となっている。振幅比による再生パワー制
御を行う場合、最初に最適な再生パワーとなる振幅比
(0.21)を検出して目標値とし、以降は随時検出し
た振幅比が目標値に近づくように制御を行うので、目標
値の検出誤差と制御用振幅比の検出誤差が合わさっても
ビットエラーレートが1E−4以下を満足するように許
容検出誤差を決める必要がある。よって振幅比の許容検
出誤差が±0.035(±0.07/2)となる条件を
考えればよい。統計学によると、平均振幅比の分布(ほ
ぼ正規分布とみなせる)の標準偏差がσの時、3σが
0.035以下であれば、99.7%以上の確率で平均
振幅比の誤差が±0.035に収まるとみなせるので、
σが0.0117(0.035/3)以下になることが
必要である。よって図7より、平均化バイト数Kは5バ
イト以上でなければならないことが分かる。On the other hand, in view of the correction capability of the error correction processing circuit used in the reproducing apparatus, it is generally considered that the bit error rate should be 1E-4 (= 1 × 10 -4 ) or less. FIG. 8 shows the results of a measurement of the relationship between the reproducing power of the semiconductor laser, the bit error rate (BER) of the reproduced binary data, and the amplitude ratio of the long and short marks, using the same reproducing apparatus as in FIG. 8, the amplitude ratio is in the range of 0.14 to 0.28, that is, 0.21 ±.
At a reproduction power of 0.07, the bit error rate is 1E-4 or less. When performing the reproduction power control based on the amplitude ratio, first, the amplitude ratio (0.21) that becomes the optimum reproduction power is detected and set as a target value, and thereafter, control is performed such that the detected amplitude ratio approaches the target value as needed. Therefore, it is necessary to determine an allowable detection error so that the bit error rate satisfies 1E-4 or less even when the detection error of the target value and the detection error of the control amplitude ratio are combined. Therefore, it is sufficient to consider a condition that the allowable detection error of the amplitude ratio is ± 0.035 (± 0.07 / 2). According to statistics, when the standard deviation of the distribution of the average amplitude ratio (which can be regarded as almost a normal distribution) is σ, and if 3σ is 0.035 or less, the error of the average amplitude ratio is ± 99.7% or more with a probability of 99.7% or more. 0.035
σ needs to be 0.0117 (0.035 / 3) or less. Therefore, it can be seen from FIG. 7 that the number of averaged bytes K must be 5 bytes or more.
【0023】ところで、上記実測の形態では、変調方式
として(1,7)RLL、短マークとして2Tcの繰り
返しパターン、長マークとして8Tcの繰り返しパター
ンを用いた場合の結果を示したが、その他の場合とし
て、変調方式をNRZI、短マークを1Tcと2Tcの
交互繰り返しパターン、長マークを8Tcの繰り返しパ
ターンとした時の実測結果を図9、図10に示す。図9
は、変調方式としてNRZIを用いた磁気的超解像光磁
気ディスク再生装置にて、平均化バイト数K’と検出さ
れた振幅比の精度(100回分の検出結果の分布の標準
偏差で表す)の関係を実測した結果である。また図10
は、同じ再生装置にて、半導体レーザの再生パワーと、
再生された二値化データのビットエラーレート(BE
R)及び長短マークの振幅比との関係を実測した結果で
ある。By the way, in the above-described actual measurement mode, the results in the case where (1,7) RLL is used as the modulation method, the 2Tc repetition pattern is used as the short mark, and the 8Tc repetition pattern is used as the long mark are shown. 9 and 10 show actual measurement results when the modulation method is NRZI, the short mark is an alternating repetition pattern of 1Tc and 2Tc, and the long mark is a repetition pattern of 8Tc. FIG.
Is the relationship between the number of averaged bytes K 'and the accuracy of the detected amplitude ratio (expressed as the standard deviation of the distribution of the detection results for 100 times) in a magnetic super-resolution magneto-optical disk reproducing apparatus using NRZI as the modulation method. Is the result of actual measurement. FIG.
In the same reproducing apparatus, the reproducing power of the semiconductor laser,
Bit error rate of reproduced binary data (BE
It is the result of actually measuring the relationship between R) and the amplitude ratio of the long and short marks.
【0024】図9より、平均化バイト数K’が25バイ
ト以上になると、標準偏差はほとんど変化していないこ
とが分かる。これは、(1,7)RLLでの40バイト
よりも小さいので、結局、平均化バイト数は40バイト
以下にすれば十分である。FIG. 9 shows that when the averaged byte number K 'is 25 bytes or more, the standard deviation hardly changes. Since this is smaller than 40 bytes in the (1,7) RLL, it is sufficient to set the averaged byte number to 40 bytes or less.
【0025】一方、(1,7)RLL変調の場合と同様
に考えると、図10で振幅比が0.23から0.38の
範囲、すなわち0.305±0.075となる再生パワ
ーにてビットエラーレートが1E−4以下となっている
ことが分かるので、振幅比の許容検出誤差が±0.03
75(±0.075/2)となる条件を考えればよい。
すなわち、平均振幅比の分布の標準偏差σが0.012
5(0.0375/3)以下になることが必要である。
よって図9より、平均化バイト数K’は5バイト以上で
なければならないことが分かる。On the other hand, considering the case of the (1, 7) RLL modulation in the same manner as in the case of the (1,7) RLL modulation, in FIG. Since it can be seen that the bit error rate is 1E-4 or less, the allowable detection error of the amplitude ratio is ± 0.03.
75 (± 0.075 / 2).
That is, the standard deviation σ of the distribution of the average amplitude ratio is 0.012.
5 (0.0375 / 3) or less.
Therefore, it can be seen from FIG. 9 that the averaged byte number K 'must be 5 bytes or more.
【0026】以上の結果をまとめると、平均化バイト数
は少なくとも5バイト以上必要であり、多くとも40バ
イト以下あれば十分である。すなわち、短マーク記録領
域と長マーク記録領域は、それぞれ5バイト以上40バ
イト以下にすればよい。このように、5バイト以上40
バイト以下で予め記録された再生パワー制御用マークを
再生し、A/D変換して平均化した信号に基づいて再生
パワーを制御するので、再生パワー制御用マークの記録
領域を小さくして光記録媒体の利用効率を向上させると
ともに、充分に高精度な再生パワーの制御を短時間で行
うことができる。To summarize the above results, the number of averaged bytes must be at least 5 bytes, and at most 40 bytes or less is sufficient. That is, each of the short mark recording area and the long mark recording area may be set to 5 bytes or more and 40 bytes or less. Thus, more than 5 bytes and 40
Since the reproduction power control mark recorded beforehand in bytes or less is reproduced, and the reproduction power is controlled based on the signal averaged by A / D conversion, the recording area of the reproduction power control mark is made smaller to perform optical recording. It is possible to improve the use efficiency of the medium and to control the reproduction power with sufficiently high accuracy in a short time.
【0027】尚、図11(a)に示すように、(1,
7)RLL変調の短マークでは4チャネルビット毎に上
下ピーク点がそれぞれ1つずつ含まれるので、1バイト
(12チャネルビット)あたりそれぞれ3サンプルの振
幅値が得られ、長マークでは16チャネルビット毎に上
下エンベロープ点がそれぞれ4つずつ含まれるので、1
バイトあたりそれぞれ3サンプルの振幅値が得られる。
また、図11(b)に示すように、NRZI変調の短マ
ークでは3チャネルビット毎に上下ピーク点がそれぞれ
1つずつ含まれるので、1バイト(8チャネルビット)
あたりそれぞれ約2.7(=8/3)サンプルの振幅値
が得られ、長マークでは16チャネルビット毎に上下エ
ンベロープ点がそれぞれ6つずつ含まれるので、1バイ
トあたりそれぞれ3サンプルの振幅値が得られる。As shown in FIG. 11A, (1,
7) In the short mark of the RLL modulation, one upper and lower peak point is included for every 4 channel bits, so that an amplitude value of 3 samples is obtained for each byte (12 channel bits), and for the long mark, every 16 channel bits. Contains four upper and lower envelope points, so
Three sample amplitude values are obtained for each byte.
Further, as shown in FIG. 11B, in the short mark of the NRZI modulation, one upper and lower peak point is included for every three channel bits, so that one byte (8 channel bits)
Approximately 2.7 (= 8/3) samples are obtained for each channel, and the long mark contains six upper and lower envelope points for every 16 channel bits. can get.
【0028】よって、(1,7)RLL変調の再生パワ
ー制御用マークの場合、1バイトの記録マークから3サ
ンプルのデジタル振幅値が得られるので、15サンプル
以上120サンプル以下のデジタル振幅値を平均化して
振幅比を求める構成としてもよい。また、NRZI変調
の再生パワー制御用マークの場合、1バイトの記録マー
クから8/3サンプルのデジタル振幅値が得られるの
で、(40/3)サンプル以上120サンプル以下のデ
ジタル振幅値を平均化して振幅比を求める構成としても
よい。Therefore, in the case of the (1,7) RLL modulation reproduction power control mark, three digital amplitude values can be obtained from a 1-byte recording mark, so that the digital amplitude values of 15 to 120 samples are averaged. It is also possible to adopt a configuration in which the amplitude ratio is obtained by converting to Also, in the case of a reproduction power control mark of NRZI modulation, a digital amplitude value of 8/3 samples can be obtained from a 1-byte recording mark, so that digital amplitude values of (40/3) samples or more and 120 samples or less are averaged. A configuration for obtaining the amplitude ratio may be adopted.
【0029】なお、上記実施の形態では、シフトレジス
タを用いて所定数のデジタル振幅値をすべて入力した後
に平均化計算を行う構成を示したが、これに限らず、入
力されるデジタル振幅値をレジスタに保持することなく
順次加算していって、最後にサンプル数で割算して平均
化する構成としてもよい。また、上記実施の形態では、
光記憶装置として光磁気ディスクの再生装置で説明した
が、これに限らず、光カード、光テープの再生装置に適
用してもよい。In the above-described embodiment, the configuration has been described in which the averaging calculation is performed after all the predetermined number of digital amplitude values are input using the shift register. However, the present invention is not limited to this. A configuration may be adopted in which the data is sequentially added without being held in the register, and finally divided by the number of samples and averaged. In the above embodiment,
The optical storage device has been described with reference to a reproducing device of a magneto-optical disk, but the present invention is not limited to this, and may be applied to a reproducing device of an optical card or an optical tape.
【0030】[0030]
【発明の効果】本発明の光記憶装置における再生光量制
御装置によれば、再生パワー制御用マークの記録領域を
小さくして光記録媒体の利用効率を向上させることがで
きると共に、充分に高精度な再生パワーの制御を行うこ
とが可能となる。According to the reproducing light quantity control device in the optical storage device of the present invention, the recording area of the reproducing power control mark can be reduced to improve the utilization efficiency of the optical recording medium and to achieve a sufficiently high precision. This makes it possible to control the reproduction power in an appropriate manner.
【0031】本発明の光記録媒体によれば、データ記録
領域を大きくできるため光記録媒体の利用効率を向上さ
せることと高精度な再生パワーの制御との両立を行うこ
とができ、さらに、再生パワー用制御マークの記録領域
をセクタ毎に分散して設けることにより、セクタ毎に再
生パワー制御ができるので、短い時間間隔で再生パワー
制御が応答し、最適再生パワーの短時間の変動に追従す
ることが可能となる。According to the optical recording medium of the present invention, since the data recording area can be enlarged, it is possible to improve the utilization efficiency of the optical recording medium and to control the reproducing power with high accuracy. By providing the recording area of the power control mark dispersedly for each sector, the reproduction power can be controlled for each sector. Therefore, the reproduction power control responds at short time intervals and follows short-term fluctuations of the optimum reproduction power. It becomes possible.
【図1】本実施の形態に係る超解像光磁気ディスク再生
装置を示す図である。FIG. 1 is a diagram showing a super-resolution magneto-optical disk reproducing apparatus according to an embodiment.
【図2】本実施の形態に係る光磁気ディスクのセクタ構
造を模式的に示す図である。FIG. 2 is a diagram schematically showing a sector structure of the magneto-optical disk according to the embodiment.
【図3】本実施の形態に係る光磁気ディスクの長マーク
の繰り返しパターンと短マークの繰返しパターンを説明
する図である。FIG. 3 is a diagram illustrating a repetition pattern of long marks and a repetition pattern of short marks according to the embodiment.
【図4】本実施の形態に係る長マークと短マークの再生
信号のA/Dサンプリング点を説明する模式図である。FIG. 4 is a schematic diagram illustrating A / D sampling points of a reproduction signal of a long mark and a short mark according to the present embodiment.
【図5】本実施の形態に係る短マークレベル検出回路6
の詳細構成を示す図である。FIG. 5 is a short mark level detection circuit 6 according to the embodiment;
FIG. 3 is a diagram showing a detailed configuration of the embodiment.
【図6】本実施の形態に係る長マークレベル検出回路7
の詳細構成を示す図である。FIG. 6 is a long mark level detection circuit 7 according to the embodiment;
FIG. 3 is a diagram showing a detailed configuration of the embodiment.
【図7】本実施の形態に係る(1,7)RLL変調を用
いた再生パワー制御用マークの、平均化バイト数と求め
られた振幅比の標準偏差との関係を示す測定結果の図で
ある。FIG. 7 is a diagram of a measurement result showing a relationship between an averaged byte number and a found standard deviation of an amplitude ratio of a reproduction power control mark using (1,7) RLL modulation according to the present embodiment. is there.
【図8】本実施の形態に係る(1,7)RLL変調を用
いた再生パワー制御用マークの、半導体レーザの再生パ
ワーと再生された二値化データのビットエラーレート及
び長短マークの振幅比との関係を示す測定結果の図であ
る。FIG. 8 shows the reproduction power of the semiconductor laser, the bit error rate of the reproduced binary data, and the amplitude ratio of the long and short marks of the reproduction power control mark using (1,7) RLL modulation according to the present embodiment. FIG. 7 is a diagram of measurement results showing the relationship
【図9】本実施の形態に係るNRZI変調を用いた再生
パワー制御用マークの、振幅比の平均化バイト数と求め
られた振幅比の標準偏差との関係を示す測定結果の図で
ある。FIG. 9 is a diagram of measurement results showing the relationship between the average number of bytes of the amplitude ratio and the obtained standard deviation of the amplitude ratio of the mark for reproducing power control using NRZI modulation according to the present embodiment.
【図10】本実施の形態に係るNRZI変調を用いた再
生パワー制御用マークの、半導体レーザの再生パワーと
再生された二値化データのビットエラーレート及び長短
マークの振幅比との関係を示す測定結果の図である。FIG. 10 shows the relationship between the reproduction power of a semiconductor laser, the bit error rate of reproduced binary data, and the amplitude ratio of long and short marks of a reproduction power control mark using NRZI modulation according to the present embodiment. It is a figure of a measurement result.
【図11】(1,7)RLL変調とNRZI変調におけ
る、長マークの繰り返しパターンと短マークの繰り返し
パターンのサンプリング点を説明する図である。FIG. 11 is a diagram for explaining sampling points of a repeated pattern of a long mark and a repeated pattern of a short mark in (1, 7) RLL modulation and NRZI modulation.
【図12】従来の光記憶装置における再生光量制御装置
の構成を示す図である。FIG. 12 is a diagram illustrating a configuration of a reproduction light amount control device in a conventional optical storage device.
1 光磁気ディスク 2 半導体レーザ 3 フォトダイオード 4 クロック生成回路 5 A/D変換器 6 短マークレベル検出回路 7 長マークレベル検出回路 8 データ再生回路 9 割算器 10 差動増幅器 11 再生パワー制御回路 DESCRIPTION OF SYMBOLS 1 Magneto-optical disk 2 Semiconductor laser 3 Photodiode 4 Clock generation circuit 5 A / D converter 6 Short mark level detection circuit 7 Long mark level detection circuit 8 Data reproduction circuit 9 Divider 10 Differential amplifier 11 Reproduction power control circuit
Claims (6)
も小さなアパーチャを再生層に発生させることにより記
録層からの記録情報を再生する光記録媒体を用い、該光
記録媒体に記録された再生パワー制御用マークからの再
生信号を検出して再生パワーを制御する制御手段を有す
る光記憶装置における再生光量制御装置において、 前記制御手段は、前記再生パワー制御用マークを5バイ
ト以上40バイト以下の範囲で再生して得られる再生信
号に基づいて再生パワーを制御することを特徴とする光
記憶装置における再生光量制御装置。1. An optical recording medium for reproducing recorded information from a recording layer by generating an aperture smaller than a light spot diameter of an irradiated light beam on the reproducing layer, and reproducing the information recorded on the optical recording medium. In a reproduction light amount control device for an optical storage device having a control means for controlling a reproduction power by detecting a reproduction signal from a power control mark, the control means sets the reproduction power control mark to a size of 5 bytes or more and 40 bytes or less. A reproduction light amount control device in an optical storage device, wherein reproduction power is controlled based on a reproduction signal obtained by reproducing in a range.
も小さなアパーチャを再生層に発生させることにより記
録層からの記録情報を再生する光記録媒体を用い、該光
記録媒体に記録された再生パワー制御用マークからの再
生信号を検出して再生パワーを制御する制御手段を有す
る光記憶装置における再生光量制御装置において、 前記制御手段は、前記再生パワー制御用マークを(40
/3)サンプル以上120サンプル以下の範囲で再生し
て得られる再生信号に基づいて再生パワーを制御するこ
とを特徴とする光記憶装置における再生光量制御装置。2. An optical recording medium for reproducing recorded information from a recording layer by generating an aperture in the reproducing layer smaller than the light spot diameter of the irradiated light beam, and reproducing the information recorded on the optical recording medium. In a reproduction light amount control device in an optical storage device having a control unit for controlling a reproduction power by detecting a reproduction signal from a power control mark, the control unit sets the reproduction power control mark to (40
/ 3) A reproduction light amount control device in an optical storage device, wherein reproduction power is controlled based on a reproduction signal obtained by reproducing in a range of not less than samples and not more than 120 samples.
複数の振幅値を平均化する平均化手段を備えることを特
徴とする請求項1または請求項2に記載の光記憶装置に
おける再生光量制御装置。3. The optical storage device according to claim 1, further comprising averaging means for averaging a plurality of amplitude values obtained by A / D converting the reproduced signal. Reproduction light amount control device.
も小さなアパーチャを再生層に発生させることにより記
録層からの記録情報を再生する光記録媒体において、 5バイト以上40バイト以下の再生パワー制御用マーク
が記録されていることを特徴とする光記録媒体。4. An optical recording medium for reproducing recorded information from a recording layer by generating an aperture smaller than a light spot diameter of an irradiated light beam in a reproducing layer, wherein a reproduction power control of 5 bytes or more and 40 bytes or less. An optical recording medium having recorded thereon a use mark.
クの繰り返しパターンと長マークの繰り返しパターンと
からなり、各繰り返しパターンは5バイト以上40バイ
ト以下であることを特徴とする請求項4に記載の光記録
媒体。5. The reproduction power control mark according to claim 4, wherein the mark includes a repetition pattern of short marks and a repetition pattern of long marks, and each repetition pattern has a length of 5 bytes or more and 40 bytes or less. Optical recording medium.
毎に設けられていることを特徴とする請求項4に記載の
光記録媒体。6. The optical recording medium according to claim 4, wherein the read power control mark is provided for each sector.
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP19236197A JP3343057B2 (en) | 1997-07-17 | 1997-07-17 | Reproduction light amount control device and optical recording medium in optical storage device |
DE69842250T DE69842250D1 (en) | 1997-06-24 | 1998-06-18 | Optical playback device and optical storage system with this device and a medium |
EP98111183A EP0887790B1 (en) | 1997-06-24 | 1998-06-18 | Optical reproducing device and optical memory system comprising the device and a medium |
KR1019980023745A KR100323175B1 (en) | 1997-06-24 | 1998-06-23 | Optical reproducing device and optical memory medium |
US09/103,869 US6288992B1 (en) | 1997-06-24 | 1998-06-24 | Optical reproducing device and optical memory medium |
US09/909,291 US6847592B2 (en) | 1997-06-24 | 2001-07-19 | Optical reproducing device and optical memory medium |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP19236197A JP3343057B2 (en) | 1997-07-17 | 1997-07-17 | Reproduction light amount control device and optical recording medium in optical storage device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH1139739A true JPH1139739A (en) | 1999-02-12 |
JP3343057B2 JP3343057B2 (en) | 2002-11-11 |
Family
ID=16290011
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP19236197A Expired - Fee Related JP3343057B2 (en) | 1997-06-24 | 1997-07-17 | Reproduction light amount control device and optical recording medium in optical storage device |
Country Status (2)
Country | Link |
---|---|
JP (1) | JP3343057B2 (en) |
KR (1) | KR100323175B1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999053489A1 (en) * | 1998-04-10 | 1999-10-21 | Sony Corporation | Information reproducing device and method |
US6584050B1 (en) | 1999-04-26 | 2003-06-24 | Sharp Kabushiki Kaisha | Optical recording device, optical reproducing device, and optical memory medium |
US6741527B2 (en) | 1999-04-26 | 2004-05-25 | Sharp Kabushiki Kaisha | Magneto-optical recording medium and magneto-optical recording and reproducing device capable of controlling reproduction power based on long recorded marks |
KR100447914B1 (en) * | 2000-12-27 | 2004-09-13 | 샤프 가부시키가이샤 | Apparatus for readout of optical recording medium |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100606679B1 (en) * | 1999-07-16 | 2006-08-01 | 엘지전자 주식회사 | Method for record control signal generating of optical record/player |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04337542A (en) * | 1991-05-13 | 1992-11-25 | Ricoh Co Ltd | Magneto-optical recording medium and magneto-optical recording method |
-
1997
- 1997-07-17 JP JP19236197A patent/JP3343057B2/en not_active Expired - Fee Related
-
1998
- 1998-06-23 KR KR1019980023745A patent/KR100323175B1/en not_active IP Right Cessation
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999053489A1 (en) * | 1998-04-10 | 1999-10-21 | Sony Corporation | Information reproducing device and method |
US6459669B1 (en) | 1998-04-10 | 2002-10-01 | Sony Corporation | Information reproducing apparatus and information reproducing method |
US6584050B1 (en) | 1999-04-26 | 2003-06-24 | Sharp Kabushiki Kaisha | Optical recording device, optical reproducing device, and optical memory medium |
US6741527B2 (en) | 1999-04-26 | 2004-05-25 | Sharp Kabushiki Kaisha | Magneto-optical recording medium and magneto-optical recording and reproducing device capable of controlling reproduction power based on long recorded marks |
KR100447914B1 (en) * | 2000-12-27 | 2004-09-13 | 샤프 가부시키가이샤 | Apparatus for readout of optical recording medium |
Also Published As
Publication number | Publication date |
---|---|
JP3343057B2 (en) | 2002-11-11 |
KR100323175B1 (en) | 2002-03-08 |
KR19990007253A (en) | 1999-01-25 |
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