JP3715531B2

JP3715531B2 - Information recording apparatus and information recording method

Info

Publication number: JP3715531B2
Application number: JP2000397301A
Authority: JP
Inventors: 昭彦土肥
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2000-12-27
Filing date: 2000-12-27
Publication date: 2005-11-09
Anticipated expiration: 2020-12-27
Also published as: JP2002197656A

Description

【０００１】
【発明の属する技術分野】
この発明は、目的の記録データに基づき光ビームの照射を制御して、目的の記録データを記録する情報記録装置及び情報記録方法に関する。
【０００２】
【従来の技術】
近年、書き換え可能な光ディスク（ＤＶＤ−ＲＡＭなど）が登場し始めている。書き換え可能な光ディスクは相変化記録膜を有しており、光ビームの照射を受けて記録マークが形成されたり消去されたりすることで、データの書き換えが可能となっている。
【０００３】
このような光ディスクに対して目的の記録データを記録する情報記録装置は、エンコード部、レーザ制御部、及びレーザ照射部などを備えている。エンコード部は、目的の記録データを所定の規則に従いエンコードする。レーザ制御部は、エンコードされた目的の記録データに基づきレーザ照射部のレーザ照射を制御する。レーザ照射部は、レーザ制御部の制御に基づきレーザを照射する。このレーザ照射部のレーザ照射により、目的の記録データが記録マークとスペース（記録マークの無い所）に置き換えられて光ディスク上に記録される。
【０００４】
【発明が解決しようとする課題】
しかし、上記した従来の情報記録装置には、記録データのエラーを検出して、記録データを補正するという機能がなく、エラーを含んだ記録データがそのまま記録されて、再生が不安定になるという問題があった。
【０００５】
仮に、記録データの一部にエラーが含まれており、そのままエラーが含まれた記録データが記録されたとしても、記録データに含まれるエラー訂正コードにより、正しい記録データを再生することができる。但し、エラー訂正コードによるエラー訂正能力には限界があり、あまりにも多くのエラーが含まれていると、エラー訂正できない場合がある。例えば、光ディスクにおける傷や埃の影響があってもエラー訂正コードによりエラー訂正できるはずが、既に記録データにエラーが含まれているためエラー訂正能力を超えてしまいエラー訂正できなくなってしまうこともありえる。また、記録データの一部にエラーが含まれることにより、記録マークの長さが極端に長くなってしまうと、トラッキングにも影響を生じかねない。
【０００６】
さらに、映像等の放送信号を受信して記録する場合には、リアルタイムレコーディングという手法が採用される。このリアルタイムレコーディングでは、ベリファイ無しで受信されたデータが連続記録される。このようなリアルタイムレコーディングにおいては、常に高い信頼性の記録データが要求される。
【０００７】
この発明の目的は、上記したような事情に鑑み成されたものであって、記録されたデータが安定して再生されるように、記録データに含まれる明らかなエラーを補正した上で記録データを記録する情報記録装置及び情報記録方法を提供することにある。
【０００８】
【課題を解決するための手段】
上記課題を解決し目的を達成するために、この発明の情報記録装置及び情報記録方法は、以下のように構成されている。
【０００９】
（１）この発明は、目的の記録データに基づき光ビームの照射を制御して、目的の記録データを記録する情報記録装置において、光ビームを照射する照射手段と、記録データに基づき前記照射手段から照射される光ビームを制御する制御手段とを備え、前記制御手段が、記録データに基づくマーク及びスペースの長さが所定の規則で定められた長さの範囲に収まるように、記録データの規則違反を検出する検出手段と、前記検出手段による規則違反の検出結果から、記録データに基づくマークの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このマークとこのマークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば、このマークの前部を延長してこのマークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正し、このマークとこのマークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍に満たない場合で、且つこのマークとこのマークの後に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば、このマークの後部を延長してこのマークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正し、記録データに基づくスペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このスペースとこのスペースの前に位置されるマークの合計長が所定の規則で定められた長さの２倍以上であれば、このスペースの前部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正し、このスペースとこのスペースの前に位置されるマークの合計長が所定の規則で定められた長さの２倍に満たない場合で、且つこのスペースとこのスペースの後に位置されるマークの合計長が所定の規則で定められた長さの２倍以上であれば、このスペースの後部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正し、記録データに基づくマークの長さが所定の規則で定められた長さの範囲の上限値１４Ｔ（Ｔ：１周期）より、さらに６Ｔ、７Ｔ、又は８Ｔ以上長いことが判明した場合には、１４Ｔ＋６Ｔ、１４Ｔ＋７Ｔ、又は１４Ｔ＋８Ｔの長さでこのマークが途切れるように記録データを補正する補正手段とを備えている。
【００１０】
（２）この発明の情報記録方法は、目的の記録データに基づき光ビームの照射を制御して、目的の記録データを記録する情報記録方法であって、記録データに基づくマーク及びスペースの長さが所定の規則で定められた長さの範囲に収まるように、記録データの規則違反を検出する検出ステップと、前記検出ステップによる規則違反の検出結果から、記録データに基づくマークの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このマークとこのマークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば、このマークの前部を延長してこのマークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する第１補正ステップと、前記検出ステップによる規則違反の検出結果から、記録データに基づくマークの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このマークとこのマークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍に満たない場合で、且つこのマークとこのマークの後に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば、このマークの後部を延長してこのマークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する第２補正ステップと、前記検出ステップによる規則違反の検出結果から、記録データに基づくスペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このスペースとこのスペースの前に位置されるマークの合計長が所定の規則で定められた長さの２倍以上であれば、このスペースの前部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する第３補正ステップと、前記検出ステップによる規則違反の検出結果から、記録データに基づくスペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このスペースとこのスペースの前に位置されるマークの合計長が所定の規則で定められた長さの２倍に満たない場合で、且つこのスペースとこのスペースの後に位置されるマークの合計長が所定の規則で定められた長さの２倍以上であれば、このスペースの後部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する第４補正ステップとを備えている。
【００１１】
（３）この発明の情報記録方法は、目的の記録データに基づき光ビームの照射を制御して、目的の記録データを記録する情報記録方法であって、記録データに基づくマーク及びスペースの長さが所定の規則で定められた長さの範囲に収まるように、記録データの規則違反を検出する検出ステップと、前記検出ステップによる規則違反の検出結果から、記録データに基づくマークの長さが所定の規則で定められた長さの範囲よりさらに長い所定長を超えることが判明した場合には、所定長でこのマークが途切れるように記録データを補正する補正ステップとを備えている。
【００１２】
【発明の実施の形態】
以下、この発明の実施の形態について図面を参照して説明する。
【００１３】
図１は、この発明の情報記録装置の一例に相当する光ディスク装置の概略構成を示すブロック図である。
【００１４】
図１に示す光ディスク装置は、光ディスク１に対して所定のデータを記録したり、光ディスク１に記録されたデータを再生したりするものである。この光ディスク装置は、ディスクモータ２、ＰＵＨ（ピックアップヘッド）３、記録データ生成部７、信号処理部９、フォーカス／トラキング制御部１０、及びエラー訂正処理部１１等を備えている。
【００１５】
ディスクモータ２は、光ディスク１を所定速度で回転させる。ＰＵＨ３は、レーザ照射部４、レーザ制御部５、光検出部６を備えている。レーザ照射部４は、光ディスクに対して照射パワーの異なる記録用光ビーム及び再生用光ビームを選択的に照射する。レーザ制御部５は、レーザ照射部４のオン／オフを制御すると共に、このレーザ照射部４から照射される光ビームの照射パワーを制御する。例えばデータ記録時において、レーザ制御部５は、基準クロック及び記録データに基づき記録用光ビームの照射タイミングを制御する。これにより、レーザ照射部から記録データが反映された記録用光ビームが照射され、結果的に、光ディスク上に記録マークとスペースに置き換えられた記録データが記録されることになる。光検出部６は、レーザ照射部５から照射された再生用光ビームの光ディスクからの反射光を検出する。
【００１６】
記録データ生成部７は、エンコード部８を備えている。記録データ生成部７は、目的の記録データにエラー訂正コードを付加する。エンコード部８は、エラー訂正コードが付加された記録データをエンコードする。最終的に、記録データ生成部７は、基準クロックとエンコードされた記録データ（基準クロックに同期）をレーザ制御部５に提供する。信号処理部９は、光検出部６で検出された反射光に反映されたデータを再生する。フォーカス／トラッキング制御部１０は、信号処理部で再生されたデータに基づきＰＵＨ３から照射される光ビームのフォーカス及びトラッキングを制御する。エラー訂正処理部１１は、信号処理部６で再生されたデータに含まれるエラー訂正コードに基づき、再生されたデータに含まれるエラーを訂正する。
【００１７】
続いて、図２を参照して、レーザ制御部５についてさらに詳しく説明する。図２に示すように、レーザ制御部５は、記録データ異常検出部５ａ、記録データ補正部５ｂ、記録波形生成部５ｃ、及びレーザドライバ５ｄを備えている。
【００１８】
記録データ異常検出部５ａには、記録データ生成部８から提供される基準クロックと記録データが入力される。この記録データ異常検出部５ａは、文字通り、記録データの異常を検出する。光ディスクに対して記録されるデータには、所定の規則がある。例えば、ＤＶＤ−ＲＡＭでは、ランレングス制限という規則が採用されている。ＤＶＤ−ＲＡＭには、ランレングス制限を満たす符号列を用いて「０」及び「１」からなるチャネルビット情報列（２値データ）が記録される。「０」及び「１」からなるチャネルビット情報列において、同一ビットの連続をランと呼ぶ。ランレングス制限符号では、「１」の連続は発生せず、「１」と「１」の間の「０」のランレングスが、例えばＮ個以上Ｍ個以下に制限される。このようなランレングス制限は、ＲＬＬ（Ｎ、Ｍ）などと略記される。因みに、ＲＬＬは、Run Length Limitedの略である。なお、１ビット＝２チャネルビットである。また、ＤＶＤ−ＲＡＭでは、チャネルビット列の「１」の位置で極性が反転するＮＲＺＩ（Non Return to Zero Inverted）記録方式が採用されている。チャネルビット表示で「１０００」のパターンは周期Ｔで表すと４Ｔとなるので４Ｔパターンと呼び、「１０００００００」のパターンは周期Ｔで表すと８Ｔとなるので８Ｔパターンと呼ぶ。ＣＤ及びＤＶＤの場合、最短周期は３Ｔと決められている。従って、１Ｔ及び２Ｔの周期しか持たないデータは、異常（単発ノイズデータ）であると判断することができる。また、ＤＶＤの場合、特殊な同期データまで含めると、最長周期は１４Ｔと決められている。従って、１５Ｔ（＝最長周期＋１チャネルビット）以上の周期を持つデータは、異常であると判断することができる。記録データ異常検出部５ａは、最短周期に満たないデータ及び最長周期を超えるデータを異常データとして検出し、異常検出結果を検出信号として出力する。
【００１９】
記録データ補正部５ｂには、記録データ生成部８から提供される基準クロックと記録データ、さらに記録データ検出部５ａにおける異常検出結果を示す検出信号が入力される。記録データ補正部５ｂは、検出信号に基づき記録データを補正する。言い換えると、異常が検出された場合には記録データを補正し、異常が検出されてない場合には記録データを補正しない。従って、この記録データ補正部５ｂから出力される記録データは、ケースバイケースで補正された記録データということになる。
【００２０】
補正の方法について具体例をあげて説明する。３Ｔに満たない周期のデータであって、データが記録マーク（光ビーム照射により記録マークが形成される部分）に相当する場合、及びデータがスペース（記録マークと記録マークの間の部分）に相当する場合の両者ともに、これら３Ｔに満たない周期のデータの前部又は後部を延長して、３Ｔに満たない周期のデータを３Ｔに補正する。つまり、３Ｔに満たない周期のデータに相当するマーク及びスペースが出現しないように、記録データが補正される。３Ｔに満たない周期のデータの前部又は後部のどちらを延長するかは、３Ｔを満たない周期のデータの前部及び後部のデータ長に応じて決定される。このことを下記（１）〜（４）にまとめる。
【００２１】
（１）記録マークの長さが所定の規則で定められた長さの範囲（３Ｔ）に満たないことが判明した場合であって、この記録マークとこの記録マークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば、この記録マークの前部を延長して、この記録マークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する。
【００２２】
（２）記録マークの長さが所定の規則で定められた長さの範囲（３Ｔ）に満たないことが判明した場合であって、この記録マークとこの記録マークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍に満たない場合で、且つこの記録マークとこの記録マークの後に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば、この記録マークの後部を延長して、この記録マークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する。
【００２３】
（３）スペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このスペースとこのスペースの前に位置される記録マークの合計長が所定の規則で定められた長さの２倍以上であれば、このスペースの前部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する。
【００２４】
（４）スペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって、このスペースとこのスペースの前に位置される記録マークの合計長が所定の規則で定められた長さの２倍に満たない場合で、且つこのスペースとこのスペースの後に位置される記録マークの合計長が所定の規則で定められた長さの２倍以上であれば、このスペースの後部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する。
【００２５】
例えば、図３（ａ）に示すように、データ（記録マーク又はスペース）の長さが、２Ｔの場合（規定の３Ｔに満たない場合）で、且つこの２Ｔのデータの前のデータが４Ｔ以上（２Ｔ＋４Ｔで規定の３Ｔの２倍以上になる）あれば、２Ｔのデータの前端を１Ｔ分、前側へシフトさせる。図３（ｂ）に示すように、この２Ｔのデータの前のデータが４Ｔに満たない場合には、２Ｔのデータの後端を１Ｔ分、後側へシフトさせる。
【００２６】
また、図４に示すように、１４Ｔを超える周期のデータであって、データが記録マークに相当する場合には１４Ｔ＋αで記録マークを中断させ、データがスペースに相当する場合には特に補正は加えない。これは、記録マークのマーク長があまりにも長くなると、正常なトラッキングに悪影響を及ぼし、隣のトラックのデータを誤消去してしまうこともありえるからである。ここでαの値について説明する。αの値としては、例えば、出現確率の高いデータ長に近い値を採用する。出現確率の高いデータ長とは、最長周期（規定範囲の上限値）の約半分である。最長周期が１４Ｔであれば、約半分の６Ｔ、７Ｔ、又は８Ｔである。つまり、１４Ｔを超える周期のデータであって、データが記録マークに相当する場合には１４Ｔ＋６Ｔ、１４Ｔ＋７Ｔ、又は１４Ｔ＋８Ｔで記録マークを中断させる。
【００２７】
記録波形生成部５ｃには、ケースバイケースで補正された記録データ、及び発光量制御信号が入力される。記録波形生成部５ｃは、入力された記録データ及び発光量制御信号に基づき記録波形信号を生成し出力する。レーザドライバ５ｄには、記録波形信号が入力される。レーザドライバ５ｄは、記録波形信号に基づきドライブ信号を生成し出力する。このドライブ信号により、レーザ照射部４の駆動が制御される。
【００２８】
次に、図５に示すフローチャートを参照して、上記説明した記録データの補正処理についてまとめる。
【００２９】
まず、記録データ異常検出部５ａにおいて、記録データの異常が検出される（ＳＴ１）。異常が検出されなければ（ＳＴ２、ＮＯ）、記録データは補正されることなく、そのまま採用される。異常が検出されると（ＳＴ２、ＹＥＳ）、異常の内容に応じて記録データが補正される。
【００３０】
記録データに基づく記録マークの長さが所定の規則で定められた長さの範囲（３Ｔ）に満たないことが判明した場合であって（ＳＴ３、ＹＥＳ）、この記録マークとこの記録マークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば（ＳＴ４、ＹＥＳ）、この記録マークの前部を延長して、この記録マークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する（ＳＴ５）。
【００３１】
記録データに基づくスペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって（ＳＴ３、ＹＥＳ）、このスペースとこのスペースの前に位置される記録マークの合計長が所定の規則で定められた長さの２倍以上であれば（ＳＴ４、ＹＥＳ）、このスペースの前部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する（ＳＴ５）。
【００３２】
記録データに基づく記録マークの長さが所定の規則で定められた長さの範囲（３Ｔ）に満たないことが判明した場合であって（ＳＴ３、ＹＥＳ）、この記録マークとこの記録マークの前に位置されるスペースの合計長が所定の規則で定められた長さの２倍に満たない場合で（ＳＴ４、ＮＯ）、且つこの記録マークとこの記録マークの後に位置されるスペースの合計長が所定の規則で定められた長さの２倍以上であれば（ＳＴ６、ＹＥＳ）、この記録マークの後部を延長して、この記録マークの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する（ＳＴ７）。この記録マークとこの記録マークの後に位置されるスペースの合計長が所定の規則で定められた長さの２倍に満たない場合は（ＳＴ６、ＮＯ）、この記録マークを無視するか（この記録マークをスペースに置き換える補正）、或いはこの記録マークを補正しない。
【００３３】
記録データに基づくスペースの長さが所定の規則で定められた長さの範囲に満たないことが判明した場合であって（ＳＴ３、ＹＥＳ）、このスペースとこのスペースの前に位置される記録マークの合計長が所定の規則で定められた長さの２倍に満たない場合で（ＳＴ４、ＮＯ）、且つこのスペースとこのスペースの後に位置される記録マークの合計長が所定の規則で定められた長さの２倍以上であれば（ＳＴ６、ＹＥＳ）、このスペースの後部を延長してこのスペースの長さが所定の規則で定められた長さの範囲に到達するように記録データを補正する（ＳＴ７）。このスペースとこのスペースの後に位置される記録マークの合計長が所定の規則で定められた長さの２倍に満たない場合は（ＳＴ６、ＮＯ）、このスペースを無視するか（このスペースを記録マークに置き換えてしまう）、或いはこのスペースを補正しない。
【００３４】
記録データに基づく記録マークの長さが所定の規則で定められた長さの上限値（１４Ｔ）＋αを超えたとき（ＳＴ８、ＹＥＳ）、１４Ｔ＋αで記録マークを中断させる（ＳＴ９）。つまり、１４Ｔ＋αを超えた部分については、スペースになるように記録データが補正される。記録データに基づくスペースの長さが所定の規則で定められた長さを超えても（ＳＴ１０、ＹＥＳ）、このスペースに対応する記録データは補正されない（ＳＴ１１）。
【００３５】
以上説明したように、所定の規則で定められた長さに満たない記録データを無視することにより、ランダムな短いノイズ（例えばロジックのヒゲノイズ）の影響を除去することができる。また、所定の規則で定められた長さ＋αを超える記録データに相当する記録マークを途中（所定の規則で定められた長さ＋α）で中断させることにより、著しく長い記録マークの発生を防止することができる。これにより、トラッキングを安定させることができ、結果的に隣のトラックにおけるデータの誤消去を防止することもできる。
【００３６】
なお、本願発明は、上記実施形態に限定されるものではなく、実施段階ではその要旨を逸脱しない範囲で種々に変形することが可能である。また、各実施形態は可能な限り適宜組み合わせて実施してもよく、その場合組み合わせた効果が得られる。更に、上記実施形態には種々の段階の発明が含まれており、開示される複数の構成要件における適当な組み合わせにより種々の発明が抽出され得る。例えば、実施形態に示される全構成要件からいくつかの構成要件が削除されても、発明が解決しようとする課題の欄で述べた課題が解決でき、発明の効果の欄で述べられている効果が得られる場合には、この構成要件が削除された構成が発明として抽出され得る。
【００３７】
【発明の効果】
この発明によれば、記録されたデータが安定して再生されるように、記録データに含まれる明らかなエラーを補正した上で記録データを記録する情報記録装置及び情報記録方法を提供できる。
【図面の簡単な説明】
【図１】この発明の情報記録装置の一例に相当する光ディスク装置の概略構成を示す図である。
【図２】図１に示す光ディスク装置に設けられたレーザ制御部の概略構成を示す図である。
【図３】所定の規則で定められた長さに満たない記録データ（記録マーク及びスペース）の補正を説明するための図である。
【図４】所定の規則で定められた長さを超える記録データ（記録マーク）の補正を説明するための図である。
【図５】この発明の記録データ補正処理を説明するためのフローチャートである。
【符号の説明】
１…光ディスク
２…ディスクモータ
３…ＰＵＨ（ピックアップヘッド）
４…レーザ照射部
５…レーザ制御部
６…光検出部
７…記録データ生成部
８…エンコード部
９…信号処理部
１０…フォーカス／トラッキング制御部
１１…エラー訂正処理部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information recording apparatus and an information recording method for recording target recording data by controlling irradiation of a light beam based on the target recording data.
[0002]
[Prior art]
In recent years, rewritable optical disks (DVD-RAM and the like) have begun to appear. A rewritable optical disc has a phase change recording film, and data can be rewritten by forming or erasing a recording mark upon irradiation with a light beam.
[0003]
An information recording apparatus that records target recording data on such an optical disc includes an encoding unit, a laser control unit, a laser irradiation unit, and the like. The encoding unit encodes target recording data according to a predetermined rule. The laser control unit controls the laser irradiation of the laser irradiation unit based on the encoded target recording data. A laser irradiation part irradiates a laser based on control of a laser control part. By the laser irradiation of the laser irradiation unit, the target recording data is replaced with a recording mark and a space (where there is no recording mark) and recorded on the optical disc.
[0004]
[Problems to be solved by the invention]
However, the conventional information recording apparatus described above does not have a function of detecting an error in the recording data and correcting the recording data, and the recording data including the error is recorded as it is, and the reproduction becomes unstable. There was a problem.
[0005]
Even if an error is included in a part of the recording data and the recording data including the error is recorded as it is, the correct recording data can be reproduced by the error correction code included in the recording data. However, there is a limit to the error correction capability based on the error correction code, and if too many errors are included, error correction may not be possible. For example, an error correction code should be able to correct an error even if the optical disk is affected by scratches or dust, but since the recorded data already contains an error, the error correction capability may be exceeded and the error correction cannot be performed. . In addition, if an error is included in a part of the recording data and the length of the recording mark becomes extremely long, tracking may be affected.
[0006]
Furthermore, when a broadcast signal such as a video is received and recorded, a technique called real-time recording is adopted. In this real-time recording, data received without verification is continuously recorded. In such real-time recording, highly reliable recording data is always required.
[0007]
The object of the present invention has been made in view of the circumstances as described above, and corrects an error that is clearly contained in the recorded data so that the recorded data can be stably reproduced. Is to provide an information recording device and an information recording method.
[0008]
[Means for Solving the Problems]
In order to solve the above problems and achieve the object, an information recording apparatus and an information recording method of the present invention are configured as follows.
[0009]
(1) According to the present invention, in an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording the target recording data, the irradiation unit for irradiating the light beam, and the irradiation unit based on the recording data Control means for controlling the light beam emitted from the recording data, and the control means controls the recording data so that the lengths of the marks and spaces based on the recording data fall within a range of lengths defined by a predetermined rule. This is a case where it is found from the detection means for detecting the rule violation and the detection result of the rule violation by the detection means that the length of the mark based on the recorded data is less than the length range defined by the predetermined rule. If the total length of this mark and the space located in front of this mark is more than twice the length defined by the prescribed rule, the front part of this mark is extended to make the length of this mark The recorded data is corrected so that it reaches the range of the length specified by the fixed rule, and the total length of this mark and the space positioned before this mark is twice the length determined by the predetermined rule. If the total length of this mark and the space located after this mark is more than twice the length defined by a predetermined rule, the rear part of this mark is extended to The recorded data is corrected so that the length reaches the range of the length defined by the predetermined rule, and the length of the space based on the recorded data is less than the length range defined by the predetermined rule. If the total length of this space and the mark located in front of this space is more than twice the length determined by a predetermined rule, the front part of this space is extended to this The length of the space is determined by the prescribed rules When the recorded data is corrected so as to reach the range of the length, and the total length of this space and the mark positioned in front of this space is less than twice the length defined by a predetermined rule, And if the total length of this space and the mark positioned after this space is more than twice the length determined by the predetermined rule, the rear part of this space is extended to make the length of this space the predetermined rule. The recording data is corrected so as to reach the range of the length determined in (1), and the length of the mark based on the recording data is larger than the upper limit value 14T (T: 1 period) of the length range defined by a predetermined rule. Further, when it is found that it is longer than 6T, 7T, or 8T, a correction means is provided for correcting the recording data so that the mark is interrupted at a length of 14T + 6T, 14T + 7T, or 14T + 8T.
[0010]
(2) The information recording method of the present invention is an information recording method for controlling the irradiation of a light beam based on target recording data to record the target recording data, and the length of the mark and space based on the recording data From the detection step of detecting a rule violation of the recorded data, and the detection result of the rule violation by the detection step, the length of the mark based on the recording data is predetermined. The total length of this mark and the space located in front of this mark is twice the length specified in the prescribed rule. If so, a first correction step for correcting the recorded data so that the front portion of the mark extends and the length of the mark reaches a range of a length defined by a predetermined rule; and the detection step If the length of the mark based on the recorded data is found to be less than the length specified by the specified rule from the result of the rule violation detection by the mark, the mark is positioned before this mark and this mark. And the total length of the space positioned after this mark and the mark is less than the length specified by the prescribed rule. If it is two times or more, a second correction step for correcting the recorded data so that the rear part of the mark extends to reach the length defined by a predetermined rule; and the detection If it is found from the detection result of the rule violation by the step that the length of the space based on the recorded data is less than the range of the length specified by the predetermined rule, this space and the position in front of this space Is If the total length of the mark is more than twice the length determined by the prescribed rule, the front part of this space is extended to reach the range of the length defined by the prescribed rule. The length of the space based on the recording data is less than the range defined by a predetermined rule based on the third correction step for correcting the recording data and the detection result of the rule violation by the detection step. If the total length of this space and the mark placed in front of this space is less than twice the length specified by the prescribed rule, and the position is located after this space and this space. If the total length of the marks to be created is more than twice the length defined by the prescribed rule, the rear part of this space is extended so that the length of this space is within the range defined by the prescribed rule. Record to reach And a fourth correction step for correcting the data.
[0011]
(3) An information recording method according to the present invention is an information recording method for controlling the irradiation of a light beam based on target recording data to record the target recording data, and the lengths of marks and spaces based on the recording data From the detection step of detecting a rule violation of the recorded data, and the detection result of the rule violation by the detection step, the length of the mark based on the recording data is predetermined. A correction step for correcting the recording data so that the mark is interrupted at a predetermined length when it is found that the predetermined length is longer than the length range defined by the above rule.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0013]
FIG. 1 is a block diagram showing a schematic configuration of an optical disc apparatus corresponding to an example of the information recording apparatus of the present invention.
[0014]
The optical disk apparatus shown in FIG. 1 records predetermined data on the optical disk 1 and reproduces data recorded on the optical disk 1. This optical disk apparatus includes a disk motor 2, a PUH (pickup head) 3, a recording data generation unit 7, a signal processing unit 9, a focus / tracking control unit 10, an error correction processing unit 11, and the like.
[0015]
The disk motor 2 rotates the optical disk 1 at a predetermined speed. The PUH 3 includes a laser irradiation unit 4, a laser control unit 5, and a light detection unit 6. The laser irradiation unit 4 selectively irradiates the optical disk with a recording light beam and a reproduction light beam having different irradiation powers. The laser control unit 5 controls on / off of the laser irradiation unit 4 and controls the irradiation power of the light beam emitted from the laser irradiation unit 4. For example, at the time of data recording, the laser controller 5 controls the irradiation timing of the recording light beam based on the reference clock and the recording data. As a result, the recording light beam reflecting the recording data is irradiated from the laser irradiation unit, and as a result, the recording data replaced with the recording mark and the space is recorded on the optical disk. The light detection unit 6 detects the reflected light from the optical disk of the reproduction light beam emitted from the laser irradiation unit 5.
[0016]
The recording data generation unit 7 includes an encoding unit 8. The recording data generation unit 7 adds an error correction code to the target recording data. The encoding unit 8 encodes the recording data to which the error correction code is added. Finally, the recording data generation unit 7 provides the reference clock and the encoded recording data (synchronized with the reference clock) to the laser control unit 5. The signal processing unit 9 reproduces data reflected in the reflected light detected by the light detection unit 6. The focus / tracking control unit 10 controls the focus and tracking of the light beam emitted from the PUH 3 based on the data reproduced by the signal processing unit. The error correction processing unit 11 corrects an error included in the reproduced data based on the error correction code included in the data reproduced by the signal processing unit 6.
[0017]
Next, the laser control unit 5 will be described in more detail with reference to FIG. As shown in FIG. 2, the laser control unit 5 includes a recording data abnormality detection unit 5a, a recording data correction unit 5b, a recording waveform generation unit 5c, and a laser driver 5d.
[0018]
A reference clock and recording data provided from the recording data generation unit 8 are input to the recording data abnormality detection unit 5a. The recording data abnormality detection unit 5a literally detects an abnormality in the recording data. There is a predetermined rule for data recorded on an optical disc. For example, a DVD-RAM employs a rule called run length restriction. In the DVD-RAM, a channel bit information sequence (binary data) composed of “0” and “1” is recorded using a code sequence satisfying the run length restriction. In a channel bit information sequence composed of “0” and “1”, a sequence of identical bits is called a run. In the run length limit code, “1” is not continuously generated, and the run length of “0” between “1” and “1” is limited to N or more and M or less, for example. Such a run length restriction is abbreviated as RLL (N, M) or the like. Incidentally, RLL is an abbreviation for Run Length Limited. Note that 1 bit = 2 channel bits. In addition, the DVD-RAM employs an NRZI (Non Return to Zero Inverted) recording method in which the polarity is inverted at the position “1” of the channel bit string. In the channel bit display, the pattern “1000” is 4T because it is 4T when represented by the period T, and the pattern “10000000” is 8T because it is 8T when represented by the period T. In the case of CD and DVD, the shortest cycle is determined to be 3T. Therefore, data having only 1T and 2T periods can be determined to be abnormal (single noise data). In the case of a DVD, the longest cycle is determined to be 14T, including special synchronization data. Therefore, data having a period of 15T (= longest period + 1 channel bit) or more can be determined to be abnormal. The recorded data abnormality detection unit 5a detects data that is less than the shortest cycle and data that exceeds the longest cycle as abnormal data, and outputs the abnormality detection result as a detection signal.
[0019]
The recording data correction unit 5b receives a reference clock and recording data provided from the recording data generation unit 8, and a detection signal indicating an abnormality detection result in the recording data detection unit 5a. The recording data correction unit 5b corrects the recording data based on the detection signal. In other words, the recording data is corrected when an abnormality is detected, and the recording data is not corrected when no abnormality is detected. Therefore, the recording data output from the recording data correction unit 5b is the recording data corrected on a case-by-case basis.
[0020]
The correction method will be described with a specific example. When the data corresponds to a recording mark (a portion where a recording mark is formed by irradiation with a light beam) and the data corresponds to a space (a portion between the recording mark and the recording mark). In both cases, the front part or the rear part of the data having a period less than 3T is extended to correct the data having a period less than 3T to 3T. That is, the recording data is corrected so that marks and spaces corresponding to data with a period less than 3T do not appear. Whether to extend the front part or the rear part of the data with a period less than 3T is determined according to the data length of the front part and the rear part of the data with a period less than 3T. This is summarized in the following (1) to (4).
[0021]
(1) When it is found that the length of the recording mark is less than the length range (3T) determined by a predetermined rule, the recording mark and the space positioned in front of this recording mark If the total length is more than twice the length determined by the prescribed rule, the front part of the recording mark is extended so that the length of the recording mark is within the range defined by the prescribed rule. The recorded data is corrected so as to arrive.
[0022]
(2) When it is found that the length of the recording mark is less than the length range (3T) defined by a predetermined rule, the recording mark and the space positioned in front of this recording mark When the total length is less than twice the length determined by the predetermined rule, and the total length of the space positioned after this recording mark and this recording mark is 2 of the length determined by the predetermined rule If it is more than double, the rear part of the recording mark is extended, and the recording data is corrected so that the length of the recording mark reaches the range of the length defined by a predetermined rule.
[0023]
(3) When it is found that the length of the space is less than the range of length defined by a predetermined rule, the total length of this space and the recording mark positioned in front of this space is a predetermined length. If it is more than twice the length specified by the rules, the front of the space is extended and the recorded data is corrected so that the length of the space reaches the range of the length specified by the predetermined rules. To do.
[0024]
(4) When it is found that the length of the space is less than the range of the length defined by a predetermined rule, the total length of this space and the recording mark positioned in front of this space is a predetermined length. When the total length of this space and the recording mark positioned after this space is not less than twice the length defined by the rules, and is not less than twice the length defined by the predetermined rules, The rear portion of the space is extended to correct the recording data so that the length of the space reaches a range of length determined by a predetermined rule.
[0025]
For example, as shown in FIG. 3A, when the length of data (record mark or space) is 2T (when it is less than the specified 3T), the data before the 2T data is 4T or more. If 2T + 4T is more than twice the specified 3T, the front end of 2T data is shifted forward by 1T. As shown in FIG. 3B, when the data before the 2T data is less than 4T, the rear end of the 2T data is shifted backward by 1T.
[0026]
As shown in FIG. 4, when the data has a period exceeding 14T and the data corresponds to a recording mark, the recording mark is interrupted at 14T + α, and when the data corresponds to a space, correction is particularly added. Absent. This is because if the mark length of the recording mark becomes too long, it will adversely affect normal tracking and the data in the adjacent track may be erroneously erased. Here, the value of α will be described. As the value of α, for example, a value close to the data length with a high appearance probability is adopted. The data length with a high appearance probability is about half of the longest cycle (the upper limit of the specified range). If the longest period is 14T, it is about half of 6T, 7T, or 8T. That is, if the data has a period exceeding 14T and the data corresponds to a recording mark, the recording mark is interrupted at 14T + 6T, 14T + 7T, or 14T + 8T.
[0027]
Recording data corrected on a case-by-case basis and a light emission amount control signal are input to the recording waveform generation unit 5c. The recording waveform generator 5c generates and outputs a recording waveform signal based on the input recording data and the light emission amount control signal. A recording waveform signal is input to the laser driver 5d. The laser driver 5d generates and outputs a drive signal based on the recording waveform signal. The drive of the laser irradiation unit 4 is controlled by this drive signal.
[0028]
Next, the recording data correction processing described above will be summarized with reference to the flowchart shown in FIG.
[0029]
First, the recording data abnormality detection unit 5a detects an abnormality of the recording data (ST1). If no abnormality is detected (ST2, NO), the recorded data is used without being corrected. When an abnormality is detected (ST2, YES), the recorded data is corrected according to the content of the abnormality.
[0030]
When it is found that the length of the recording mark based on the recording data is less than the length range (3T) defined by a predetermined rule (ST3, YES), this recording mark and the recording mark If the total length of the spaces positioned at is greater than or equal to twice the length determined by a predetermined rule (ST4, YES), the front portion of this recording mark is extended so that the length of this recording mark is predetermined. The recording data is corrected so as to reach the length range defined by the rule (ST5).
[0031]
When it is found that the length of the space based on the recording data is less than the range of the length defined by a predetermined rule (ST3, YES), this space and the recording mark positioned in front of this space If the total length of the space is more than twice the length determined by the predetermined rule (ST4, YES), the front of this space is extended and the length of this space is determined by the predetermined rule. The recording data is corrected so as to reach the range (ST5).
[0032]
When it is found that the length of the recording mark based on the recording data is less than the length range (3T) defined by a predetermined rule (ST3, YES), this recording mark and the recording mark When the total length of the space positioned at the position is less than twice the length defined by a predetermined rule (ST4, NO), and the total length of the space positioned after this recording mark and this recording mark is If it is more than twice the length determined by the predetermined rule (ST6, YES), the rear part of the recording mark is extended so that the length of the recording mark is within the length determined by the predetermined rule. The recorded data is corrected so as to reach (ST7). When the total length of this recording mark and the space positioned after this recording mark is less than twice the length determined by a predetermined rule (ST6, NO), this recording mark is ignored (this recording mark) Correction for replacing a mark with a space) or this recording mark is not corrected.
[0033]
When it is found that the length of the space based on the recording data is less than the range of the length defined by a predetermined rule (ST3, YES), this space and the recording mark positioned in front of this space Is less than twice the length defined by the predetermined rule (ST4, NO), and the total length of this space and the recording mark located after this space is determined by the predetermined rule. If the length of the space is more than twice (ST6, YES), the rear portion of the space is extended to correct the recorded data so that the length of the space reaches a range defined by a predetermined rule. (ST7). If the total length of this space and the recording mark located after this space is less than twice the length defined by a predetermined rule (ST6, NO), this space is ignored (this space is recorded) Or replace this space.
[0034]
When the length of the recording mark based on the recording data exceeds the upper limit value (14T) + α defined by a predetermined rule (ST8, YES), the recording mark is interrupted at 14T + α (ST9). That is, the recording data is corrected so that a portion exceeding 14T + α becomes a space. Even if the length of the space based on the recording data exceeds the length defined by a predetermined rule (ST10, YES), the recording data corresponding to this space is not corrected (ST11).
[0035]
As described above, the influence of random short noise (for example, logic whiskers) can be eliminated by ignoring the recording data that does not satisfy the length defined by a predetermined rule. Further, by interrupting the recording mark corresponding to the recording data exceeding the length defined by the predetermined rule + α in the middle (length defined by the predetermined rule + α), the occurrence of a remarkably long recording mark is prevented. be able to. As a result, tracking can be stabilized, and as a result, erroneous erasure of data in an adjacent track can be prevented.
[0036]
Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention in the implementation stage. In addition, the embodiments may be appropriately combined as much as possible, and in that case, the combined effect can be obtained. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the column of the effect of the invention Can be obtained as an invention.
[0037]
【The invention's effect】
According to the present invention, it is possible to provide an information recording apparatus and an information recording method for recording recording data after correcting an obvious error included in the recording data so that the recorded data is stably reproduced.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of an optical disc apparatus corresponding to an example of an information recording apparatus of the present invention.
FIG. 2 is a diagram showing a schematic configuration of a laser control unit provided in the optical disc apparatus shown in FIG.
FIG. 3 is a diagram for explaining correction of recording data (recording marks and spaces) that is less than a length defined by a predetermined rule.
FIG. 4 is a diagram for explaining correction of recording data (recording marks) exceeding a length determined by a predetermined rule.
FIG. 5 is a flowchart for explaining recording data correction processing according to the present invention;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical disk 2 ... Disk motor 3 ... PUH (pickup head)
DESCRIPTION OF SYMBOLS 4 ... Laser irradiation part 5 ... Laser control part 6 ... Light detection part 7 ... Recording data generation part 8 ... Encoding part 9 ... Signal processing part 10 ... Focus / tracking control part 11 ... Error correction processing part

Claims

In an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording target recording data,
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
When it is found from the detection result of the rule violation by the detection means that the length of the mark based on the recorded data is less than the length range defined by the predetermined rule, the length of the mark is the predetermined length. When the record data is corrected so as to reach the length range specified by the rules, and the length of the space based on the record data is found to be less than the length range specified by the predetermined rules Correcting means for correcting the recording data so that the length of the space reaches the range of the length determined by a predetermined rule;
An information recording apparatus comprising:

In an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording target recording data,
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
If it is found from the detection result of the rule violation by the detection means that the length of the mark based on the recorded data is less than the length defined by the predetermined rule, it is positioned before and after this mark. Depending on the length of the space, the length before or after this mark is extended to correct the recorded data so that the length of this mark reaches the range defined by a predetermined rule. If it is found that the length of the space based on the recorded data is less than the length range defined by a predetermined rule, the space length depends on the length of the mark positioned before and after this space. Correction means for correcting the recording data so that the length of the space reaches the range of the length determined by a predetermined rule by extending the length of the front or back;
An information recording apparatus comprising:

In an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording target recording data,
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
The detection result of the rule violation by the detection means indicates that the length of the mark based on the recorded data is less than the length range defined by a predetermined rule, and this mark and the mark If the total length of the spaces located at is more than twice the length determined by the prescribed rule, the front part of this mark is extended and the length of this mark is the length defined by the prescribed rule The recorded data is corrected so as to reach the range of this mark, and the total length of this mark and the space positioned in front of this mark is less than twice the length defined by a predetermined rule, and this mark If the total length of the space located after this mark is more than twice the length determined by the predetermined rule, the rear part of this mark is extended and the length of this mark is determined by the predetermined rule. Recorded to reach a range of lengths The data is corrected, and it is found that the length of the space based on the recorded data is not within the range of the length defined by a predetermined rule, and the mark positioned before this space and this space If the total length of the space is more than twice the length determined by the predetermined rule, the front part of the space is extended to reach the range of the length determined by the predetermined rule. When the total length of this space and the mark positioned in front of this space is less than twice the length defined by a predetermined rule, and after this space and this space, If the total length of the marks to be positioned is more than twice the length determined by the predetermined rule, the rear part of the space is extended and the length of the space is within the length range determined by the predetermined rule. The recorded data is supplemented to reach And correction means for,
An information recording apparatus comprising:

In an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording target recording data,
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
When it is found from the detection result of the rule violation by the detection means that the length of the mark based on the recorded data exceeds a predetermined length longer than the range of the length defined by the predetermined rule, the predetermined length Correction means for correcting the recording data so that the mark is interrupted;
An information recording apparatus comprising:

In an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording target recording data,
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
When it is found from the detection result of the rule violation by the detection means that the length of the mark based on the recorded data is longer than the upper limit value L of the length range defined by a predetermined rule, by more than L / 2 Correcting means for correcting the recording data so that the mark is interrupted at a length of L + L / 2;
An information recording apparatus comprising:

In an information recording apparatus for controlling the irradiation of a light beam based on target recording data and recording target recording data,
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
From the detection result of the rule violation by the detection means, the length of the mark based on the recording data is further 6T, 7T, or 8T from the upper limit value 14T (T: 1 period) of the length range defined by a predetermined rule. If it is found that the length is longer than the above, a correction means for correcting the recording data so that the mark is interrupted at a length of 14T + 6T, 14T + 7T, or 14T + 8T;
An information recording apparatus comprising:

An apparatus for recording target recording data by an NRZI recording method, wherein the target recording data is recorded by controlling irradiation of a light beam based on the target recording data.
An irradiation means for irradiating a light beam;
Control means for controlling the light beam emitted from the irradiation means based on recorded data;
With
The control means is
Detecting means for detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data falls within a range of the length determined by a predetermined rule;
The detection result of the rule violation by the detection means indicates that the length of the mark based on the recorded data is less than the length range defined by a predetermined rule, and this mark and the mark If the total length of the spaces located at is more than twice the length determined by the prescribed rule, the front part of this mark is extended and the length of this mark is the length defined by the prescribed rule The recorded data is corrected so as to reach the range of this mark, and the total length of this mark and the space positioned in front of this mark is less than twice the length defined by a predetermined rule, and this mark If the total length of the space located after this mark is more than twice the length determined by the predetermined rule, the rear part of this mark is extended and the length of this mark is determined by the predetermined rule. Recorded to reach a range of lengths The data is corrected, and it is found that the length of the space based on the recorded data is not within the range of the length defined by a predetermined rule, and the mark positioned before this space and this space If the total length of the space is more than twice the length determined by the predetermined rule, the front part of the space is extended to reach the range of the length determined by the predetermined rule. When the total length of this space and the mark positioned in front of this space is less than twice the length defined by a predetermined rule, and after this space and this space, If the total length of the marks to be positioned is more than twice the length determined by the predetermined rule, the rear part of the space is extended and the length of the space is within the length range determined by the predetermined rule. The recorded data is supplemented to reach If the mark length based on the recorded data is found to be 6T, 7T, or 8T longer than the upper limit value 14T (T: 1 period) of the length range defined by a predetermined rule. , 14T + 6T, 14T + 7T, or 14T + 8T, a correction means for correcting the recording data so that the mark is interrupted.
An information recording apparatus comprising:

An information recording method for controlling the irradiation of a light beam based on target recording data and recording target recording data,
A detection step of detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data is within the range of the length defined by a predetermined rule;
When it is determined from the detection result of the rule violation by the detection step that the length of the mark based on the recorded data is less than the length range defined by the predetermined rule, the length of the mark is the predetermined length. When the record data is corrected so as to reach the length range specified by the rules, and the length of the space based on the record data is found to be less than the length range specified by the predetermined rules A correction step for correcting the recording data so that the length of the space reaches the range of the length determined by a predetermined rule;
An information recording method comprising:

An information recording method for controlling the irradiation of a light beam based on target recording data and recording target recording data,
A detection step of detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data is within the range of the length defined by a predetermined rule;
The detection result of rule violation by the detection step is a case where it is found that the length of the mark based on the recorded data is less than the length range defined by a predetermined rule, and this mark and the mark If the total length of the spaces located at is more than twice the length determined by the prescribed rule, the front part of this mark is extended and the length of this mark is the length defined by the prescribed rule A first correction step for correcting the recording data so as to reach the range of
The detection result of rule violation by the detection step is a case where it is found that the length of the mark based on the recorded data is less than the length range defined by a predetermined rule, and this mark and the mark When the total length of the space located at is less than twice the length determined by the predetermined rule, and the total length of the space positioned after this mark and this mark is determined by the predetermined rule A second correction step of correcting the recorded data so that the length of the mark reaches the range of the length defined by a predetermined rule by extending the rear part of the mark if the length is twice or more of the length; ,
It is found from the detection result of the rule violation by the detection step that the length of the space based on the recorded data is less than the length range defined by a predetermined rule, and this space and the space before this space If the total length of the marks placed in is more than twice the length determined by the prescribed rule, the front of this space is extended and the length of this space is the length defined by the prescribed rule A third correction step for correcting the recording data so as to reach the range of
It is found from the detection result of the rule violation by the detection step that the length of the space based on the recorded data is less than the length range defined by a predetermined rule, and this space and the space before this space When the total length of the mark located in the space is less than twice the length determined by the predetermined rule, and the total length of the mark positioned after this space and this space is determined by the predetermined rule A fourth correction step for correcting the recorded data so that the length of the space reaches the range of the length determined by a predetermined rule by extending the rear portion of the space if the length is twice or more of the length; ,
An information recording method comprising:

An information recording method for controlling the irradiation of a light beam based on target recording data and recording target recording data,
A detection step of detecting a violation of the rule of the record data so that the length of the mark and the space based on the record data is within the range of the length defined by a predetermined rule;
When it is found from the detection result of the rule violation by the detection step that the length of the mark based on the recorded data exceeds a predetermined length longer than the range of the length defined by the predetermined rule, the predetermined length A correction step for correcting the recording data so that the mark is interrupted;
An information recording method comprising: