569197 A7 B7 五、發明説明（η ) 1 ·發明領域 (請先閲讀背面之注意事項再填寫本頁) 本發明·係關於因應提供記錄之資料，多階段切換照射 雷射光束之照射時間以及照射功率之至少其中一方，可以 進行多級記錄資料之光記錄媒體及光記錄方法。 2 .習知技術 對於如習知之光記錄媒體之藉由多階段改變再生信號 之長度（反射信號調變部之長度）以記錄資料之方法，有 很多關於藉由多階段切換再生信號之深度（反射信號之調 變度），在相同長度之各信號記錄複數的資料之方法的硏 究。 經濟部智慧財產局員工消費合作社印製 如依據此光記錄方法，與單單記錄藉由凹點之有無的 2値之資料的情形相比，在深度方向可以記錄複數的資料 之故，可以增加分配在一定之長度的信號量，因此，可以 提升線記錄密度。多階段切換再生信號之深度的方法，一 般有多階段切換雷射光束之功率，形成某種種類不同之言己 錄標記。現在，該記錄媒體有提案利用雷射照相術者和使 記錄層成爲多層者。 又，此處稱如反射信號之調變度多階段地變化般地以 記錄各資料爲多級記錄。 另一方面，這些多級記錄隨著記錄時之雷射光束的功 率變大，即隨著形成之反射信號深度變深，有再生時之信 號品質劣化之問題。此理由雖然尙未淸楚，但是本發明者 之預測認爲其原因係由於雷射功率之增加，記錄標記之面 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） -4- 569197 A7 B7 五、發明説明（2 ) 積（記錄標記區域）增大。 (請先閲讀背面之注意事項再填寫本頁) 例如，爲了記錄媒體之記錄資訊量的高密度化，使記 錄標記變短，其中’多段切換雷射之功率而多級記錄之情 形，該信號品質之劣化變得顯著，結果爲無法活用多級記 錄之優點。即如採用多級記錄，必須使記錄標記之間隔變 寬，即使信號品質劣化，也必須可以某種程度進行資料檢 測。 又，如習知般地，在階段地切換雷射功率以達成多級 記錄之思想下，記錄標記長度成爲比記錄時之聚光光束（ 光束腰身）之直徑還大。一般聚光光束之直徑係以Κλ /ΝΑ(Κ :常數、λ :雷射波長、ΝΑ ··透鏡之數値孔徑値）表 示。例如，在光記錄媒體爲CD(緻密光碟）時，在此CD所 利用之光拾取頭中，一般爲；I = 780nm、NA = 0.45，聚光光 束之直徑爲1.6 // m。在此情形，記錄標記長一成爲1.6 # m 附近，上述信號劣化之問題變得顯著，以改變雷射功率之 方法進行5階段以上之多級記錄有困難。 經濟部智慧財產局員工消費合作社印製 以上之問題雖認爲係雷射光束之功率設定、記錄媒體 之特性等之所有因素複雜糾纏之結果，但是據本發明者所 知，其原因現在還不淸楚，現在實情爲高密度之多級記錄 包含該記錄媒體以及記錄方法尙未達成。 發明摘要 本發明係有鑑於上述問題而完成者，藉由將記錄媒體 之特性設定在指定之狀態，提案新的多級記錄手法，以達 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -5 - 569197 A7 ___B7 ___ 五、發明説明（3 ) 成高密度之多級記錄爲目的。 (請先閲讀背面之注意事項再填寫本頁) 本發明者關於光記錄媒體重覆專心硏究，發現記錄層 係假定一定尺寸之假想記錄單元，藉由於此形成尺寸不同 之記錄標記，多階段調變假想記錄單元全體之反射率之多 階段記錄方法；藉由此記錄方法，確認可以在光記錄媒體 進行5階段以上之高密度的多級記錄。 即藉由以下之本發明，可以達成上述目的。 經濟部智慧財產局員工消費合作社印製 (1 ) 一種藉由對於形成在光透過性基板上之記錄層， 照射雷射光束，形成記錄標記，可以記錄資訊之光記錄媒 體，其特徵爲：在前述光記錄媒體之記錄標記形成區域於 與前述雷射光束之相對移動方向連續規定指定的單位長以 及與其正交之方向的指定單位寬之複數的假想記錄單元， 同時，在前述假想記錄單元的前述雷射光束未照射狀態之 初期反射率爲X%，以及在該雷射光束已經照射狀態，形成 最大記錄標記時之界限最低反射率爲Y%之情形，前述假想 記錄單元之特性設定爲（X-Y) /X在0.3以上，理想爲0.4以 上，對於該假想記錄單元，5階段以上切換前述雷射光束的 照射時間以及照射功率之至少其中一方以進行多級記錄。 (2 )如（1 )之光記錄媒體，其中前述假想記錄單元 在藉由5階段以上切換前述雷射光束的照射時間以及照射功 率之至少其中一方以多級記錄而形成記錄標記時，在各階 段之反射率的全記錄標記形成區域之偏差設定爲5%以內， 理想爲3%以內之特性。 (3 )如（1 )或（2 )之光記錄媒體，其中前述假想記 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） -6- 569197 A7 ____ B7 五、發明説明（4 ) 錄單元之特性係設定爲（X-Y)/XS 0.9。 (4 ) 一種對藉由對於形成在光透過性基板上之記錄層 ，照射雷射光束以形成記錄標記，可以記錄資訊之光記錄 媒體之光記錄方法，其特徵爲：在前述光記錄媒體之記錄 標記形成區域於與前述雷射光束之相對移動方向連續規定 指定的單位長以及與其正交之方向的指定單位寬之複數的_ 假想記錄單元，同時，在前述假想記錄單元的前述雷射光 束未照射狀態之初期反射率爲X%，以及在該雷射光束已經 照射狀態，形成最大記錄標記時之界限最低反射率爲Y%之 情形，前述假想記錄單元之特性設定爲（X-Y) /X在0.3以 上，理想爲0.4以上，對於該假想記錄單元，5階段以上切換 前述雷射光束的照射時間以及照射功率之至少其中一方以 進行多級記錄。 (5)如（4)之光記錄方法，其中前述假想記錄單元在藉 由5階段以上切換前述雷射光束的照射時間以及照射功率之 至少其中一方以多級記錄而形成記錄標記時，在各階段之 反射率的全記錄標記形成區域之偏差設定爲5%以內，理想 爲3%以內之特性。 (6 )如（4 )或（5 )之光記錄方法，其中前述假想記 錄單元之特性係設定爲（X-Y)/XS 0.9。 本發明者著眼於光記錄媒體之在前述假想記錄單元之 反射率的變動特性與多級記錄手法兩方。特別是注目在反 射率之動態範圍以及/或者同一記錄等級之反射率的偏差 ，前者如在一定値以上以及/或者後者在指定値之範圍內 本紙張尺度適用中國國家標準（CNS ) Α4規格（210X297公釐） (請先閱讀背面之注意事項再填寫本頁) 、?τ 經濟部智慧財產局員工消費合作社印製 ί__ -7- 569197 A7 B7 五、發明説明（5) ，知道可以進行更爲良好之多級記錄。 (請先閱讀背面之注意事項再填寫本頁) 依據本發明者之解析，爲了良好進行具有假想記錄單 元之5階段以上的反射率變動之多級記錄，在記錄標記使反 射率降低之情形，形成最大限度的記錄標記之情形的假想 記錄單元之反射率與完全不形成記錄標記之情形的假想記 錄單元之反射率之差（動態範圍）需要某種程度之差，此 動態範圍之値在多級記錄之情形，各信號之反射率等級如 不具有某種程度之間隔，各信號彼此之反射率會成爲干涉 之狀態，知道會對記錄再生帶來妨礙。 因此，爲了不受到此種信號間干涉之影響以進行良好 之記錄再生，在進行種種檢討後，特別是爲了進行5階段以 上之多級記錄，藉由最適當化溝形狀和記錄層膜厚等之種 種構造，了解到需要設定動態範圍在某値以上。 實際測量之結果，動態範圍在30%以上，理想爲40%以 上時，可以良好進行5階段以上之多級記錄。特別是，假想 記錄單元之設定長度在比光束直徑短之情形，其效果更爲 顯著。 經濟部智慧財產局員工消費合作社印製 進而，在同一記錄區域內，在多級記錄之各階段中， 需要使反射率之偏差小於習知之2値記錄。 在此同一記錄區域內之反射率的偏差雖可以藉由多級 記錄之段數而設定，但是在5階段以上之多級記錄之情形， 知道設上述偏差在5 %以內爲佳。更好爲在3 %以下。此種5階 段以上之多級記錄之情形，動態範圍雖以大者爲佳，但是 如太大，會產生信號失真之故，上限係在上述之範圍。 i紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐) " -8- 569197 經濟部智慧財產局員工消費合作社印製 A7 B7五、發明説明（6 ) 合適實施例之詳細說明 以下，參考圖面詳細說明本發明之實施形態之例子。 本發明之實'施形態之例.的光記錄媒體（光碟）10係在 記錄層12使用色素之CD-R(追加記錄型緻密光碟），包含 由透明基材形成之基板14 ;及在此基板14之一面（圖1之上 面）覆蓋在光碟中心周圍形成爲螺旋狀或者同心圓狀之雷 射光束導引用之溝1 6而塗佈的色素所形成之前述記錄層1 2 :及藉由濺鍍等形成在此記錄層12之上側之金或者銀等之 反射膜1 8 ;及覆蓋此反射膜1 8之外側之保護層20而形成。 使用在前述記錄層12之色素係花青系色素、部花青、 甲撐系色素以及其之衍生物、苯羧酸金屬絡合物、苯二甲 藍色素、柰花青色素、偶氮色素等之有機色素。 對前述光記錄媒體10之多級記錄係藉由圖2所示之光記 錄裝置30而實行。 此光記錄裝置30係CD-R記錄器，透過主軸伺服31藉由 主軸馬達32以線速度一定之條件旋轉驅動光記錄媒體（光 碟）10，藉由由雷射36來之雷射光束，在光記錄媒體（光 碟）10記錄資訊。 前述雷射36係因應應記錄資訊，藉由雷射驅動器38控 制圖3所示之假想記錄單元（詳細後述）40之每一個之雷射 光束照射時間，例如，雷射脈衝數、以及/或者照射功率 ，例如脈衝高度。 圖2之標號42係包含物鏡42A以及半透明透過42B之記 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） -9- 569197 經濟部智慧財產局員工消費合作社印製 A7 B7 _五、發明説明（7 ) 錄光學系統。物鏡42A係藉由聚焦追跡伺服44，控制聚焦追 跡以使雷射光束聚光在光碟10之記錄.層12。又，物鏡42 A與 半透明透鏡42B係藉由進給伺服46與光碟10之旋轉同步，控 制由其內側往外側以指定速度移動。 前述主軸伺服3 1、雷射驅動器38、聚焦追跡伺服44、 禁止伺服46係由控制裝置50所控制。應記錄在記錄層12之 資料（資訊）係輸入控制裝置50。 又，在調變雷射光束之照射功率之情形，在前述脈衝 高度之控制外，也可以利用如圖2以2點虛線所示般地，在 雷射光束之光路徑上配置光調變器4 1，藉由控制裝置50以 控制其之手段。 接著，說明前述假想記錄單元40以及記錄在此假想記 錄單元40之記錄標記。 此假想記錄單元40係如圖1所示般地，係在前述溝1 6內 於光碟34之旋轉方向，即圓周方向連續地規定。各假想記 錄單元40之圓周方向S之長度Η係如圖3所示般地，設定爲 比光束直徑（光束腰身之直徑）D還短，藉由對每一假想 記錄單元40照射雷射光束，因應應記錄資訊而形成模型地 顯示之記錄標記48Α〜48G。 具體爲藉由適當使由前述雷射36所射出之雷射光束的 雷射照射時間變化，在雷射光束之中心部形成直徑不同之 記錄標記48Α〜48G (雷射光束雖係圓形，但是由於係一面使 光碟10旋轉一面照射雷射光束之故，記錄標記成爲因應照 射時間長度之長圓形。又，記錄標記之寬也因應照射時間 本紙張尺度適用中國國家標準（CNS ) A4規格（210 X 297公釐） (請先閱讀背面之注意事項再填寫本頁) -10- 569197 經濟部智慧財產局員工消費合作社印製 A7 B7_五、奁明説明（8 ) 與照射功率而變大）。. 爲何呢？此係被聚焦之雷射光束一般雖成爲高斯分布 ，但是在記錄層1 2中，只以雷射光束之照射能量超過某臨 界値之部份進行記錄之故，藉由使雷射光束之照射時間以 及/或者照射功率變化，可以記錄在記錄層1 2之雷射光束 的光點尺寸也隨著變化之故。藉由此，例如可以形成圖3所 示之7階段的記錄標記48A〜48G。 在此情形，記錄標記48A〜48G之各大小（面積）設設 定爲對假想記錄單元40照射讀出雷射光束時之反射光的光 反射率成爲7階段。前述光反射率係記錄標記愈小而成爲愈 大，在沒有形成記錄標記之假想記錄單元中，成爲最大反 射率，在形成最大的記錄標記4 8 G之假想記錄單元中，成爲 最小反射率。更詳細爲前述光反射率係考慮對於各記錄標 記48A〜48G之假想記錄單元40的面積比以及記錄標記本身 之光透過率而設定。 記錄標記48A〜48G本身之光透過率在構成記錄層12之 材料由於雷射光束之照射而分解變質，其折射率變化之情 形，或者由於記錄層1 2之厚度方向的變化量而不同。如形 成之記錄標記部份之光透過率爲零，可以不考慮及此。 接著，說明此光碟10之特性。 在此光碟1 0中，在設假想記錄單元40之前述雷射光束 未照射狀態之初期反射率爲X%，而且，藉由（某種程度長 時間）照射雷射光束而到達界限，形成最大的記錄標記時 之反射率（最低反射率）爲Y%之情形，前述假想記錄單元 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） ~ 一 -11 - (請先閲讀背面之注意事項再填寫本頁) 569197 經濟部智慧財產局員工消費合作社印製 A7 _B7____五、發明説明（9 ) 40之特性設定爲（X-Y) /X在0.3以上，理想爲0.4以上。或 者（X-Y) /X即使最大也設定在0·9ν 進而，在此實施形態之光碟1 0中，前述假想記錄單元 40在藉由5階段以上切換前述雷射光束之照射時間而多級記 錄以形成記錄標記時，在各階段之反射率的全記錄區域（ 記錄區域）之偏差設定爲5%以內，理想爲3%以內之特性。 具體爲調整設定假想記錄單元40之面積、記錄層12之 材料、雷射光束之光束腰身之直徑D。例如，對於假想記 錄單元40，如使記錄標記之大小更大，反射率之動態範圍 變大，而且，反射率之偏差也變大。 如上述般地，藉由就光碟1 0之特性進行設定，在5階段 以上之多級記錄之情形，各記錄階段之差，即假想記錄單 元40之反射率的各階段之絕對値之差可以嚴格區別各記錄 階段（記錄標記）。 上述動態範圍雖係藉由變更溝1 6之寬和深度而改變， 但是在色素記錄媒體之情形，由於色素狀態（色素層本身 之厚度與色素對於溝深度之厚度等）等而不同之故，爲了 滿足各種特性，需要一面使其最適當化，一面確保動態範 圍。 在本發明之多級記錄中，動態範圍如在0.3以上，理想 爲0.4以上，可以進行錯誤少之記錄再生，也可以使抖動値 降低。進而，未記錄徑向對比、拉挽信號等也可以一倂獲 得良好之値。 這些之理想値係未記錄徑向對比在0.02以上、push-pull (請先閱讀背面之注意事項再填寫本頁j -訂 本紙張尺度適用中國國家標準（CNS ) A4規格（21〇Χ：Ζ97公釐） -12- 569197 經濟部智慧財產局員工消費合作社印製 A7 B7五、發明説明（1C)) 在 0.03以上，wobble to noise ration30dB 以上。 又，動態範圍之上限値雖然愈大愈好’但是’動態範 圍如太大，在對假想記錄單元40之反射率變低的標記的相 對反射率的偏差極端增加。由於相對反射率之偏差增加’ 信號讀取錯誤率（一般稱爲錯誤率）變大之故’爲了防止 此，以（X-Y ) 〇·9爲理想。 進而，多級記錄之記錄標記48A〜48G之長度即使在讀 取雷射之聚光光束腰身的直徑D以下’也可以確實檢測資 料。 其結果爲可以5階段以上反射率不同地產生聚光光束腰 身以下之極小的記錄標記之故’可以獲得極高記錄密度之 光記錄媒體。 又在上述發明中，前述光記錄媒體之前述記錄層以包 含有機色素成分而構成爲佳。實際上’如後述之例子所說 明般地，藉由有機色素成分之反應以產生記錄標記之方法 ，以達成上述之多級記錄。 又在本實施形態之例子中，如上述般地，雖顯示光記 錄媒體10爲CD-R之構成，但是本發明並不限定於此，夜噁 以適用在其它之光記錄媒體，而且’也不是限定在碟狀之 旋轉體。 又，在上述實施形態之例子中，記錄層1 2雖係使用花 青等之有機色素，但是本發明並不限定於此，只要可以滿 足上述反射率之動態範圍以及/或者反射率之偏差的特性 者即可，也可以爲上述以外之有機色素或者無機材料，而 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -13- 569197 經濟部智慧財產局員工消費合作社印製 A7 B7五、發明説明（Μ) 且也可以適當使用其它之材料。但是，在使用如上述之有 機色素之情形，對應雷射光束之5階段以上之照射時間，可 以確實使記錄標記之大小變化而進行記錄，可以以極高的 精度進行讀取。 進而，上述實施形態之例子雖係關於包含未記錄資料 等之資訊之未記錄區域之光記錄媒體10，但是，本發明並 不限定於此，也可以適用5階段以上進行資訊之多級記錄之 光記錄媒體。 進而，在藉由上述光記錄裝置30以形成記錄標記之際 ，設定在記錄層12上之假想記錄單元40之尺寸並不限定於 實施形態之例子。另一方面，在8階段等更多階段記錄記錄 標記之情形，也可以設定在雷射光束腰身以上。在該情形 ，某一部份之記錄標記可以在光束腰身以上之大小。進而 ，不具有溝16之光記錄媒體也可以適用本發明。 又，記錄用之雷射光束雖在記錄層12之位置係設爲圓 形，但是此如圖4所示般地，例如在物鏡42Α之外，藉由加 上光束整型稜鏡42C或者縫隙（省略圖示）等，可以作成光 束形狀在記錄媒體10之進給方向短，在與其正交方向成爲 長的長圓形或者線狀。在此情形，記錄標記49變短之故， 可以使假想記錄單元更短。即可以提高記錄密度。 進而，在此光記錄媒體10中，如圖1中以標號52所示般 地，也可以使之具有預先配合信號調變之段數的數目之反 射率不同的複數的凹點，或者在該光記錄媒體之一部份預 先如前述般地，進行多級記錄。可以在這些複數的凹點52 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) Α4規格（210Χ297公釐） -14- 569197 A 7 B7 經濟部智慧財產局員工消費合作社印製 五、發明説明（12) 以及/或者多級記錄完畢部份之記錄標記54記錄個別辨識 該記錄媒體之資訊、辨識係多級記錄用光記錄媒體之資訊 、決定記錄再生該記錄媒體用之雷射光束的推薦記錄功率 之資訊等的特性資訊。該特定資訊藉由在該光記錄媒體再 生以及/或者記錄時進行讀取，可以確實辨識其係多級記 錄用光記錄媒體，進而，個別辨識彼等，因應預先記錄之 凹點的段數，可以決定雷射光束的照射時間，可以進行更 確實之多級記錄、再生。 或者如圖1中標號56所示般地，藉由設置使雷射光束導 引用之溝一部份中途斷掉之溝中斷部，也可以使具有同樣 之效果。這些方法可以單獨或者組合利用。 (例） 以下與比較例一齊顯示本發明之例子。此例以及比較 例之具體條件如下： 記錄媒體10係製作在記錄層使用色素之CD-R型之光記 錄媒體，進行多級記錄之實驗。 如下述表1所示般地，藉由改變形成在光透過性基板之 溝的寬度’種種變更動態範圍。記錄雷射功率爲1 3 mW、溝 深爲200nm、色素膜厚對溝深之厚度爲70%程度。 (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -15- 569197 A7 B7 五、發明説明（） 13’ (表1 ) \ 溝寬（n m ) 動態範圍 (X-Y) /X 錯誤 SDR(%) 判定 比較例1 310 0.24 6.15 3.63 i良 例1 350 0.31 4.28 1.86 例2 480 0.41 3.19 1.51 又，·如表2般地，藉由改變形成在光透過性基板之溝的 深度’種種變更動態範圍。記錄雷射功率爲1 3mW、溝深爲 350nm、色素對於溝深之膜厚爲70%程度、記錄時之線速度 爲 9.6 m / s。 (請先聞讀背面之注意事項再填寫本頁) (表2) \ 溝深（nm) 動態範圍 (X-Y ) /X 錯誤 SDR(%) 判定 比較例2 160 0.28 5.72 3.77 i良 例3 180 0.32 3.68 1.79 例4 200 0.41 2.57 1.55 經濟部智慧財產局員工消費合作社印製 此處，溝深係由存在於溝間之島部的最高位置與溝底 部之最低位置算出。又，溝寬係在上述溝深的一半値的位 置測量。進而，色素厚度係將光記錄媒體在光碟半徑方向 切斷，由掃描型電子顯微鏡觀察測量溝、島橫穿方向剖面 。記錄再生裝置係使用改造CD-R/RW用之泛用驅動裝置， 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -16- 569197 A7 B7 五、發明説明（14) 在動態範圍之測量上係藉由使用HP (惠普）公司製造之數 位示波器而測量之反射率所求得。 (請先閲讀背面之注意事項再填寫本頁) 又，表1、表2之錯誤係確認記錄之信號是否可以良 好再生之指標，將由惠普公司製造之數位示波器所獲得之 fe威取入電腦而使之3十算以算出錯誤値。此値係本身請專 利人獨自之指標，如在5.00以下，可以判斷爲能夠進行良好 之記錄再生，如超過此値，記錄再生變得極端不穩定，會 有記錄再生不良之問題。 進而，此處所言之SDR係由多級之各階段的反射率與 動態範圍所求得之各階段的信號的偏差。（以動態範圍正 常化反射率之標準偏差σ之値）此偏差如小，不用說可以 進行良好之信號的記錄再生。如依據本發明者之實驗，此 SDR値如在5%以下即算理想，如在3%以下更爲理想。此處 ，以2%以下爲目標。 經濟部智慧財產局員工消費合作社印製 在本發明之多級記錄中，如上述結果般地，動態範圍 如在0.3以上，理想爲0.4以上，可以進行錯誤少之記錄再生 ，抖動値也可以低。進而，反射率、推挽信號等也一倂可 以獲得良好之値。 如依據本發明，可以獲得適用在5階段以上之新的多級 記錄手法而可確實檢測資料之光記錄媒體。而且，該記錄 標記之長度可以包含讀取雷射之聚光光束（光束腰身）之 直徑以下者之故，能夠飛躍提升資訊的記錄密度。 圖面之簡單說明 本紙張尺度適用中國國家標準（CNS ) Α4規格（210 X 297公釐） -17- 569197 A 7 B7 五、發明説明（15) 第1圖係顯示本發明之實施形態之例之光記錄媒體的重 要部位之一部份剖面的斜視圖。 第2圖係顯示在同一光記錄媒體利用雷射光束以記錄資 訊用之光記錄裝置之方塊圖。 第3圖係顯示藉由同一光記錄媒體在記錄層形成記錄標 記之際的該記錄標記與假想記錄單元以及其之光反射率之 關係模型圖。 第4圖係顯示使照射假想記錄單元之雷射光束成爲其它 形狀之情形的簡略顯示斜視圖。 主要元件對照 (請先聞讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 10 光 記 錄 媒 體 12 記 錄 層 14 基 板 16 溝 18 反射 膜 20 保 護 層 30 光 記 錄 裝 置 31 主 軸 伺 服 32 主 軸 馬 達 36 雷 射 38 雷 射 驅 動 器 40 假 想 記 錄 單 元 44 聚 焦追 跡 伺 服 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -18- 569197 A7 B7五、發明説明（16)46 進給伺服50 控制裝置 (請先閲讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） -19-569197 A7 B7 V. Description of the invention (η) 1 · Field of invention (please read the precautions on the back before filling out this page) The present invention is related to the provision of recorded information, switching the irradiation time and irradiation of the laser beam in multiple stages At least one of the powers can perform an optical recording medium and an optical recording method for multilevel recording data. 2. Conventional technology For conventional optical recording media, there are many methods for changing the length of the reproduction signal (the length of the reflection signal modulation section) to record data. There are many ways to switch the depth of the reproduction signal by multi-stage ( Modulation of the reflected signal), research on the method of recording complex data for each signal of the same length. According to this light recording method, printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, compared with the case of simply recording 2 资料 data with the presence or absence of pits, multiple data can be recorded in the depth direction, which can increase distribution The semaphore at a certain length, therefore, can increase the line recording density. The method of switching the depth of the reproduced signal in multiple stages generally involves switching the power of the laser beam in multiple stages to form a recorded mark of some kind. The recording medium now has proposals for using laser photographers and making recording layers into multiple layers. Here, it is referred to as a multi-level recording in which each data is recorded as the modulation degree of the reflected signal changes in multiple stages. On the other hand, with these multi-level recordings, as the power of the laser beam at the time of recording becomes larger, that is, as the depth of the formed reflected signal becomes deeper, there is a problem that the signal quality at the time of reproduction deteriorates. Although this reason is not clear, but the inventor's prediction believes that the reason is due to the increase in laser power, the paper size of the recording mark applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) -4 -569197 A7 B7 V. Description of the invention (2) The product (recording mark area) is increased. (Please read the precautions on the back before filling this page.) For example, in order to increase the recording information volume of the recording medium, the recording mark is shortened. In the case of 'multi-stage switching laser power and multi-level recording, this signal The deterioration in quality becomes significant, and as a result, the advantage of multilevel recording cannot be utilized. That is, if multi-level recording is used, the interval between recording marks must be widened, and even if the signal quality is degraded, it is necessary to be able to perform data detection to some extent. In addition, as is conventionally known, under the idea that laser power is switched in stages to achieve multi-level recording, the recording mark length becomes larger than the diameter of the condensing beam (beam waist) during recording. In general, the diameter of a condensing beam is represented by κλ / ΝΑ (κ: constant, λ: laser wavelength, NA ·· number of lenses 値 aperture 値). For example, when the optical recording medium is a CD (Compact Disc), the optical pickup head used by this CD is generally: I = 780nm, NA = 0.45, and the diameter of the condensing beam is 1.6 // m. In this case, as long as the recording mark becomes 1.6 # m long, the above-mentioned problem of signal degradation becomes significant, and it is difficult to perform multi-level recording of more than 5 stages by changing the laser power. The above problems printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs are considered to be the result of complicated entanglement of all factors such as the power setting of the laser beam and the characteristics of the recording medium. However, as far as the present inventors know, the reason is not yet However, it is true that the high-density multi-level recording including the recording medium and the recording method have not yet been achieved. Summary of the Invention The present invention was completed in view of the above problems, and by setting the characteristics of the recording medium in a specified state, a new multi-level recording method was proposed to meet the Chinese paper standard (CNS) A4 standard (210X297) (Mm) -5-569197 A7 ___B7 ___ 5. Description of the invention (3) The purpose is to create a high-density multi-level record. (Please read the precautions on the back before filling this page) The inventor repeatedly studied the optical recording medium and found that the recording layer is a hypothetical recording unit of a certain size. Due to this, recording marks of different sizes are formed in multiple stages. A multi-stage recording method for modulating the reflectance of the entire virtual recording unit; with this recording method, it is confirmed that high-density multi-stage recording of 5 steps or more can be performed on an optical recording medium. That is, the above-mentioned object can be achieved by the following invention. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs (1) A light recording medium capable of recording information by irradiating a laser beam to a recording layer formed on a light-transmitting substrate, which can record information, is characterized by: The recording mark formation area of the optical recording medium is a plurality of imaginary recording units that continuously specify a specified unit length and a specified unit width in a direction orthogonal to the relative movement direction of the laser beam. In the case where the initial reflectance of the laser beam in the unirradiated state is X%, and in the case where the laser beam has been irradiated, the minimum reflectance at the limit when forming the maximum recording mark is Y%, and the characteristics of the aforementioned imaginary recording unit are set to ( XY) / X is 0.3 or more, and ideally 0.4 or more. For this imaginary recording unit, at least one of the irradiation time and irradiation power of the laser beam is switched in 5 steps or more to perform multi-level recording. (2) The optical recording medium according to (1), wherein when the virtual recording unit switches the irradiation time and irradiation power of the laser beam in at least one of 5 stages, the recording mark is formed in each stage when the recording mark is formed in multiple stages. The deviation of the fully recorded mark formation area of the reflectance at each stage is set to be within 5%, and ideally within 3%. (3) An optical recording medium such as (1) or (2), in which the aforementioned imaginary paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) -6- 569197 A7 ____ B7 V. Description of the invention ( 4) The characteristics of the recording unit are set to (XY) / XS 0.9. (4) An optical recording method for an optical recording medium capable of recording information by irradiating a laser beam to a recording layer formed on a light-transmitting substrate to form a recording mark, which is characterized in that: In the recording mark formation area, a plurality of _ hypothetical recording units that continuously specify a specified unit length and a specified unit width in a direction orthogonal to the relative movement direction of the laser beam, and the laser beam in the virtual recording unit. The initial reflectance of the unirradiated state is X%, and when the laser beam has been irradiated, the minimum reflectance at the limit when forming the maximum recording mark is Y%. The characteristics of the aforementioned imaginary recording unit are set to (XY) / X It is 0.3 or more, and preferably 0.4 or more. For this virtual recording unit, at least one of the irradiation time and the irradiation power of the laser beam is switched in 5 steps or more to perform multi-level recording. (5) The optical recording method according to (4), wherein when the imaginary recording unit switches the irradiation time and irradiation power of the laser beam by at least one of five stages to form recording marks in multiple stages, The deviation of the fully recorded mark formation area of the reflectance at each stage is set to be within 5%, and ideally within 3%. (6) The optical recording method according to (4) or (5), wherein the characteristics of the aforementioned imaginary recording unit are set to (X-Y) / XS 0.9. The present inventors focused on both the change characteristics of the reflectance of the optical recording medium in the aforementioned virtual recording unit and the multilevel recording method. In particular, the deviation in the dynamic range of the reflectance and / or the reflectance of the same recording level, if the former is above a certain threshold and / or the latter is within a specified threshold, the Chinese paper standard (CNS) Α4 specification ( 210X297 mm) (Please read the precautions on the back before filling out this page),? Τ Printed by the Consumer Consumption Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs __ -7- 569197 A7 B7 V. Description of the invention (5) Good multi-level record. (Please read the precautions on the back before filling this page.) According to the analysis by the inventor, in order to properly perform the multilevel recording of the reflectance change with more than 5 stages of the imaginary recording unit, when the recording mark reduces the reflectance, The difference (dynamic range) between the reflectance of the imaginary recording unit in the case where the maximum recording mark is formed and the imaginary recording unit in the case where the recording mark is not formed at all requires a certain degree of difference. In the case of high-level recording, if the reflectance level of each signal does not have a certain interval, the reflectivity of each signal will interfere with each other, and it is known that it will hinder recording and reproduction. Therefore, in order to perform good recording and reproduction without being affected by such inter-signal interference, after conducting various reviews, especially to perform multi-level recording of more than 5 stages, the groove shape and the recording layer film thickness are optimally optimized. All kinds of structures, I understand that you need to set the dynamic range above a certain threshold. As a result of actual measurement, when the dynamic range is above 30%, ideally above 40%, multi-level recording of more than 5 stages can be performed well. In particular, when the set length of the imaginary recording unit is shorter than the beam diameter, the effect is more remarkable. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Furthermore, in the same recording area, in each stage of the multi-level recording, the deviation of the reflectance should be smaller than the conventional 2 値 record. Although the deviation of the reflectance in the same recording area can be set by the number of stages of multi-level recording, in the case of multi-level recording of more than 5 stages, it is better to know that the above-mentioned deviation is within 5%. More preferably, it is below 3%. In the case of multi-level recording of more than 5 stages, although the dynamic range is preferably larger, if it is too large, signal distortion will occur, and the upper limit is in the above range. i Paper size applies Chinese National Standard (CNS) A4 specification (210X297 mm) " -8- 569197 Printed by A7 B7, Consumer Cooperative of Intellectual Property Bureau, Ministry of Economic Affairs 5. Description of invention (6) The detailed description of suitable embodiments is as follows, An example of an embodiment of the present invention will be described in detail with reference to the drawings. An example of the embodiment of the present invention. An optical recording medium (optical disc) 10 is a CD-R (additional recording type compact disc) using a pigment in the recording layer 12 and includes a substrate 14 formed of a transparent substrate; and here One side of the substrate 14 (top of FIG. 1) covers the above-mentioned recording layer 1 2 formed by the pigment coated with a groove 16 that is formed as a spiral or concentric circular laser beam guide around the center of the optical disc: and by A reflective film 18 made of gold, silver, or the like is formed on the upper side of the recording layer 12 by sputtering or the like; and a protective layer 20 is formed to cover the outer side of the reflective film 18. Pigment-based cyanine-based pigments, merocyanine, methylene-based pigments and derivatives thereof used in the recording layer 12 described above, benzoic acid metal complexes, xylylene blue pigment, cyanine pigment, and azo pigments And other organic pigments. The multi-level recording of the aforementioned optical recording medium 10 is performed by the optical recording device 30 shown in Fig. 2. This optical recording device 30 is a CD-R recorder. The optical recording medium (optical disc) 10 is rotationally driven by a spindle servo 31 and a spindle motor 32 at a constant linear speed, and a laser beam from a laser 36 is used in Optical recording media (disc) 10 records information. In response to the recording information, the aforementioned laser 36 controls the laser beam irradiation time of each of the virtual recording units (described in detail later) 40 shown in FIG. 3 by the laser driver 38, for example, the number of laser pulses, and / or Irradiation power, such as pulse height. The reference numeral 42 in FIG. 2 includes the objective lens 42A and the translucent transmission 42B (please read the precautions on the back before filling out this page) This paper size applies to the Chinese National Standard (CNS) A4 specification (210X 297 mm) -9- 569197 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 _V. Description of Invention (7) Recording optical system. The objective lens 42A is controlled by the focus tracking servo 44 to control the focus tracking so that the laser beam is focused on the recording layer 12 of the optical disc 10. In addition, the objective lens 42 A and the translucent lens 42B are synchronized with the rotation of the optical disc 10 by the feed servo 46 and controlled to move from the inside to the outside at a specified speed. The aforementioned spindle servo 31, the laser driver 38, the focus tracking servo 44, and the prohibition servo 46 are controlled by the control device 50. The data (information) to be recorded in the recording layer 12 is input to the control device 50. In addition, in the case of modulating the irradiation power of the laser beam, in addition to the aforementioned control of the pulse height, an optical modulator may be arranged on the optical path of the laser beam as shown by a two-dotted dotted line in FIG. 2. 4 1. Means for controlling it by the control device 50. Next, the aforementioned hypothetical recording unit 40 and the recording marks recorded in this hypothetical recording unit 40 will be described. This imaginary recording unit 40 is continuously defined in the rotation direction of the optical disc 34, that is, in the circumferential direction, as shown in Fig. 1. The length S in the circumferential direction S of each virtual recording unit 40 is set to be shorter than the beam diameter (the diameter of the beam waist) D as shown in FIG. 3. By irradiating a laser beam to each virtual recording unit 40, In accordance with the record information, record marks 48A to 48G are displayed in a model. Specifically, by appropriately changing the laser irradiation time of the laser beam emitted by the laser 36, recording marks 48A to 48G having different diameters are formed in the center of the laser beam (although the laser beam is circular, but Because the laser beam is irradiated while the disc 10 is rotated, the recording mark becomes an oval corresponding to the length of the irradiation time. Also, the width of the recording mark also corresponds to the irradiation time. This paper size applies the Chinese National Standard (CNS) A4 specification ( 210 X 297 mm) (Please read the precautions on the back before filling this page) -10- 569197 Printed by A7 B7_5, Ming Ming Instructions (8) and irradiation power by the Intellectual Property Bureau Staff Consumer Cooperatives of the Ministry of Economic Affairs ). Why? Although this focused laser beam generally has a Gaussian distribution, in the recording layer 12, only the part where the irradiation energy of the laser beam exceeds a certain threshold is used for recording. By irradiating the laser beam As time and / or irradiation power change, the spot size of the laser beam that can be recorded in the recording layer 12 changes as well. With this, for example, the 7-stage recording marks 48A to 48G shown in FIG. 3 can be formed. In this case, the respective sizes (areas) of the recording marks 48A to 48G are set so that the light reflectance of the reflected light when the virtual recording unit 40 is irradiated with the read laser beam becomes seven steps. The aforementioned light reflectance is smaller as the recording mark becomes larger, and becomes the maximum reflectance in an imaginary recording unit where no recording mark is formed, and becomes the minimum reflectance in an imaginary recording unit where the largest recording mark is 4 8 G. More specifically, the light reflectance is set in consideration of the area ratio of the imaginary recording unit 40 for each of the recording marks 48A to 48G and the light transmittance of the recording marks themselves. The light transmittance of the recording marks 48A to 48G itself is degraded due to the irradiation of the laser beam by the material constituting the recording layer 12, and the refractive index changes, or the amount of change in the thickness direction of the recording layer 12 varies. If the light transmittance of the formed recording mark portion is zero, this can be ignored. Next, the characteristics of the optical disc 10 will be described. In this optical disc 10, the initial reflectance of the above-mentioned laser beam irradiated state of the imaginary recording unit 40 is set to X%, and the laser beam is irradiated (to some extent for a long time) to reach the limit, forming a maximum When the reflectance (lowest reflectance) at the time of recording marks is Y%, the paper size of the aforementioned imaginary recording unit applies the Chinese National Standard (CNS) A4 specification (210X297 mm) ~ 1-11-(Please read the Note: Please fill in this page again.) 569197 Printed by A7 _B7____ of the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. The characteristics of invention description (9) 40 are set to (XY) / X above 0.3, ideally above 0.4. Or (XY) / X is set to 0 · 9ν even at the maximum. Furthermore, in the optical disc 10 of this embodiment, the virtual recording unit 40 records the laser beam in multiple stages by switching the irradiation time of the laser beam in 5 stages or more. When forming a recording mark, the deviation of the total recording area (recording area) of the reflectance at each stage is set to a characteristic within 5%, and ideally within 3%. Specifically, the area D of the imaginary recording unit 40, the material of the recording layer 12, and the beam waist diameter D of the laser beam are adjusted. For example, for the virtual recording unit 40, if the size of the recording mark is made larger, the dynamic range of the reflectance becomes larger, and the deviation of the reflectance becomes larger. As described above, by setting the characteristics of the optical disc 10, in the case of multi-level recording of 5 stages or more, the difference between the recording stages, that is, the absolute difference between the stages of the reflectance of the imaginary recording unit 40 can be Strictly distinguish each recording stage (recording mark). Although the above dynamic range is changed by changing the width and depth of the groove 16, in the case of a pigment recording medium, the state of the pigment (the thickness of the pigment layer itself and the thickness of the pigment with respect to the depth of the groove, etc.) are different. In order to satisfy various characteristics, it is necessary to optimize the range while ensuring the dynamic range. In the multilevel recording of the present invention, if the dynamic range is 0.3 or more, ideally 0.4 or more, recording and reproduction with few errors can be performed, and jitter 値 can be reduced. Furthermore, even if no radial contrast, pull-pull signal, etc. are recorded, good results can be obtained at once. These ideals are not recorded with a radial contrast of more than 0.02, push-pull (please read the notes on the back before filling in this page j-The size of the paper is applicable to the Chinese National Standard (CNS) A4 specification (21〇 ×: Z97) (Mm) -12- 569197 A7 B7 printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. The invention description (1C)) is above 0.03, and wobble to noise ration is above 30dB. Although the upper limit of the dynamic range 値 is larger, the better, but the dynamic range is too large, and the deviation of the relative reflectance with respect to marks whose reflectance becomes lower in the virtual recording unit 40 is extremely increased. Since the deviation of the relative reflectance increases, the signal reading error rate (commonly referred to as the error rate increases). In order to prevent this, (X-Y) 0.9 is preferable. Furthermore, even if the length of the recording marks 48A to 48G in the multi-level recording is less than the diameter D of the waist of the focused beam of the laser beam, the data can be reliably detected. As a result, it is possible to generate extremely small recording marks below the waist of the condensing beam with different reflectances of 5 steps or more. 'An optical recording medium with extremely high recording density can be obtained. In the above invention, the recording layer of the optical recording medium is preferably configured to include an organic pigment component. Actually, as explained in the example described later, the method of generating a recording mark by the reaction of the organic pigment components achieves the above-mentioned multilevel recording. In the example of this embodiment, as described above, although the optical recording medium 10 is shown as a CD-R structure, the present invention is not limited to this, and the night evil is applicable to other optical recording media, and 'also It is not limited to a disk-shaped rotating body. Moreover, in the example of the above embodiment, although the recording layer 12 is an organic pigment such as cyanine, the present invention is not limited to this, as long as the dynamic range of the reflectance and / or the deviation of the reflectance can be satisfied. Those who have special characteristics can be organic pigments or inorganic materials other than the above, and (please read the precautions on the back before filling this page) This paper size is applicable to China National Standard (CNS) A4 (210X297 mm) -13 -569197 A7 B7 printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of Invention (M) and other materials may be used as appropriate. However, in the case of using the organic pigment as described above, the recording time can be changed with the change of the size of the recording mark in accordance with the irradiation time of 5 steps or more of the laser beam, and the reading can be performed with extremely high accuracy. Furthermore, although the example of the above-mentioned embodiment relates to the optical recording medium 10 of an unrecorded area containing information such as unrecorded data, the present invention is not limited to this, and it is also applicable to multi-level recording of information in five or more stages. Optical recording medium. Furthermore, when the recording mark is formed by the optical recording device 30, the size of the virtual recording unit 40 set on the recording layer 12 is not limited to the example of the embodiment. On the other hand, the recording marks may be recorded at more stages such as 8 stages, and may be set above the waist of the laser beam. In this case, a part of the recording mark may be the size above the waist of the beam. Furthermore, the present invention can be applied to an optical recording medium having no groove 16. In addition, although the laser beam for recording is circular at the position of the recording layer 12, as shown in FIG. 4, for example, the beam shaping 稜鏡 42C or the gap is added to the objective lens 42A, for example. (The illustration is omitted.) The shape of the light beam may be short in the feed direction of the recording medium 10, and may be long oval or linear in the direction orthogonal thereto. In this case, since the recording mark 49 becomes shorter, the imaginary recording unit can be made shorter. That is, the recording density can be increased. Furthermore, in this optical recording medium 10, as shown by reference numeral 52 in FIG. 1, it is also possible to have a plurality of pits having different numbers of reflectances in accordance with the number of segments to which the signal is modulated in advance, or A part of the optical recording medium is previously subjected to multi-level recording as described above. Can be in these multiple dents 52 (Please read the notes on the back before filling this page) This paper size applies the Chinese National Standard (CNS) A4 specification (210 × 297 mm) -14- 569197 A 7 B7 Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the employee's consumer cooperative V. Description of the invention (12) and / or the record mark 54 of the multi-level recording completion part records the information that individually identifies the recording medium, identifies the information of the multi-level recording optical recording medium, and decides to record and reproduce the Information about the characteristics of the recommended recording power of the laser beam used in the recording medium. By reading the specific information during reproduction and / or recording of the optical recording medium, the specific information can be reliably identified as a multi-level optical recording medium for recording, and further, they can be individually identified according to the number of pits recorded in advance, The irradiation time of the laser beam can be determined, and more accurate multilevel recording and reproduction can be performed. Alternatively, as shown by reference numeral 56 in FIG. 1, a groove interrupting portion that interrupts a part of the groove guided by the laser beam can be provided with the same effect. These methods can be used individually or in combination. (Examples) Examples of the present invention are shown below together with comparative examples. The specific conditions of this example and the comparative example are as follows: The recording medium 10 is a CD-R type optical recording medium using a pigment in a recording layer, and an experiment of multilevel recording is performed. As shown in Table 1 below, the dynamic range is changed by changing the width of the groove formed in the light-transmitting substrate. The recorded laser power was 13 mW, the groove depth was 200 nm, and the pigment film thickness to groove depth thickness was about 70%. (Please read the precautions on the back before filling this page) This paper size applies to Chinese National Standard (CNS) A4 specification (210X297 mm) -15- 569197 A7 B7 V. Description of the invention () 13 '(Table 1) \ groove Wide (nm) Dynamic range (XY) / X Error SDR (%) Judgment Comparative Example 1 310 0.24 6.15 3.63 i Good example 1 350 0.31 4.28 1.86 Example 2 480 0.41 3.19 1.51 Also, as shown in Table 2, by changing The depth of the groove formed in the light-transmitting substrate changes the dynamic range in various ways. The recording laser power was 13 mW, the groove depth was 350 nm, the film thickness of the pigment to the groove depth was about 70%, and the linear velocity at the time of recording was 9.6 m / s. (Please read the notes on the back before filling this page) (Table 2) \ Groove depth (nm) Dynamic range (XY) / X Error SDR (%) Judgment Comparative Example 2 160 0.28 5.72 3.77 i Good example 3 180 0.32 3.68 1.79 Example 4 200 0.41 2.57 1.55 Printed here by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the depth of the ditch is calculated from the highest position of the island in the trench and the lowest position of the bottom of the trench. The groove width is measured at a position which is half of the groove depth. Further, the thickness of the pigment was cut in the radial direction of the optical recording medium, and the measurement groove and island cross-section in the radial direction were observed with a scanning electron microscope. The recording and reproduction device is a general-purpose drive device for rebuilding CD-R / RW. This paper size is applicable to China National Standard (CNS) A4 specification (210X297 mm) -16- 569197 A7 B7 V. Description of the invention (14) The measurement of the range is obtained by measuring the reflectance using a digital oscilloscope manufactured by HP. (Please read the precautions on the back before filling this page.) In addition, the errors in Tables 1 and 2 are indicators to confirm whether the recorded signals can be reproduced well. The power obtained from the digital oscilloscope manufactured by Hewlett-Packard Company is taken into the computer. Make it 30 to calculate the error 値. This is an index that the patentees themselves ask. If it is below 5.00, it can be judged that good recording and reproduction can be performed. If it exceeds this value, the recording and reproduction become extremely unstable and there will be problems of poor recording and reproduction. Further, the SDR referred to here is the deviation of the signal of each stage obtained from the reflectance of each stage of the multi-stage and the dynamic range. (The standard deviation σ of the normalized reflectance of the dynamic range is normal.) If this deviation is small, it goes without saying that a good signal can be recorded and reproduced. According to the experiments of the inventors, this SDR is ideal if it is below 5%, and even more ideal if it is below 3%. Here, the target is 2% or less. The Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs printed the multi-level records of the present invention. As the above results, the dynamic range is above 0.3, ideally above 0.4. Records can be reproduced with few errors, and jitter can be low. . Furthermore, the reflectance, push-pull signal, etc. can also be obtained at a glance. According to the present invention, it is possible to obtain an optical recording medium capable of reliably detecting data by applying a new multi-level recording method of 5 stages or more. In addition, the length of the recording mark can include the reading of the diameter of the focused light beam (beam waist) of the laser, which can greatly increase the recording density of information. Brief description of the drawing The paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) -17- 569197 A 7 B7 V. Description of the invention (15) Figure 1 shows an example of the embodiment of the present invention A perspective view of a cross section of one of the important parts of the optical recording medium. Fig. 2 is a block diagram showing an optical recording device for recording information using a laser beam on the same optical recording medium. Fig. 3 is a model diagram showing the relationship between the recording mark and the virtual recording unit and the light reflectance when the recording mark is formed on the recording layer by the same optical recording medium. Fig. 4 is a schematic perspective view showing a case where a laser beam irradiating a virtual recording unit is formed into another shape. Comparison of main components (please read the precautions on the back before filling out this page) Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs Employee Cooperatives 10 Optical recording media 12 Recording layer 14 Substrate 16 Groove 18 Reflective film 20 Protective layer 30 Optical recording device 31 Spindle Servo 32 Spindle motor 36 Laser 38 Laser driver 40 Imaginary recording unit 44 Focus tracking servo This paper size applies to Chinese National Standard (CNS) A4 specification (210X297 mm) -18- 569197 A7 B7 V. Description of invention (16) 46 Feed servo 50 control device (please read the precautions on the back before filling this page) Printed by the Employees' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) -19-