1310180 九、發明說明： 【發明所屬之技術領域】 本發明係關於用於相變化光碟之記錄方法，尤其是更 關於（但不限於）用於調整相變化光碟之雷射寫入脈衝之方 法，其目的在於增進重覆記錄之品質。 【先前技術】 隨著以一整合性方式處理包括動態或靜態圖片、音頻 資料及電腦資料之多媒體世代的來臨，諸如CD及DVD之 封裝媒體的使用已急遽增加且可預期將朝此路徑發展。諸 如藍光雷射（Blu-ray)光碟（BD)之新型高密度光碟已快速地 發展中，且新型光碟相關產品預期可在不久的將來於市場 上供應。 一如CD、DVD或BD之封裝媒體至少包含一基材、 一記錄層及一保護層。一唯讀光碟具有形成於其上提供伺 服/位置資訊及資料之預製凹坑，且具有一反射層。 一可記錄或可重寫光碟具有一可記錄染料或一相變化 或磁光記錄層，及一保護層，其用以保護該記錄層及預製 凹坑與一反射層。可記錄或可重寫光碟兼可用作音頻或視 頻儲存媒體，及作用為電腦資料儲存媒體。當一光碟係用 作一電腦儲存媒體時，該光碟應比用作一視頻或一音頻資 料儲存媒體實行更多資料重寫。 對於記錄及播放資料，由一雷射二極體放射之雷射光 束在通過一物鏡後到達一反射層、一透明保護層（聚碳酸鹽 5 1310180 基材，其用於CD之厚度為1.2毫米而DVD為0.6毫米） 及一記錄層，且已反射之雷射光束係由一光二極體收集。 在藍光雷射光碟之案例中，會使用一在405奈米單一波長 處操作之藍光雷射及一 0.85之高數值孔徑（NA)的物鏡，且 厚度0.6毫米之保護層係由一厚度0.1毫米之覆蓋層取代。 該記錄層可根據雷射照射而藉由相變化成為非晶性或 結晶性。非晶性記號及結晶性間距在光反射中顯示一實質 上之差異，且因此其可用以表示二進制資料。因為積聚了 熱量，一單一雷射脈衝無法形成一形狀完整之非晶性記 號。基於此_原因，顯示在第1圖中之多脈衝（multi pulses) 係通常用以形成非晶性記號。 第1圖示範用於相變化光碟之習知寫入脈衝的波形。 在記錄期間，雷射輸出係依據一預定寫入策略以三種不同 功率位準加以調變。寫入功率pw(其為最高雷射功率）在記 錄層上產生非晶性狀態。抹除功率P e (其為中間功率）熔化 該記錄層且將其轉換成一結晶性狀態。底部功率 Pb係最 低雷射功率位準。 在圖中，FP、LE、MP、LP分别表示第一脈衝、前導 抹除功率持續時間、多脈衝或中心脈衝及雷射脈衝。TE表 示與N R ZI結束位置之尾緣（t r a i 1 i n g e d g e)冷卻時間偏差。 例如，3FT表示3T記號之第一脈衝，4MP至8MP表示4T 至8Τ記號之多脈衝，2ΤΕ表示2Τ記號之尾緣冷卻時間偏 差，4LP至8LP表示4Τ至8Τ記號之最後脈衝。 已知用以製造 BD之共熔基材料係以成長為主要方 6 1310180 式，且非晶性區域之形狀敏感地隨寫入脈衝之寬度、 及時序而變化。 第2 a圖示範用以形成2 T至8 T記號之習知寫入 的波形，其中每一 MP及LP之上升緣係與一參考時脈 升緣同步。第2b圖示範由寫入脈衝形成之2T至8T 的照片。在一記號之尾緣部份的非晶性及結晶性區域 邊界，比在其前導部份更易於區別。因此，當由該雷 描一記號時，其尾緣部份顯示更高之光反射，且結果 導部份獲得較佳之抖動（jitter)。 在寫入相期間，該記錄層被加熱至炫點上，且此 接著快速冷卻，允許該等原子以非晶性狀態凝固。除 卻速率係足夠高，結晶性材料會從邊界成長，減少了 性區域。 由習知寫入策略形成之記號的前導部份顯示已減 晶性區域，因為來自4T至8T記號之第一脈衝（4FP至 後的多脈衝（4M至8M)降低了冷卻速率。結果，在一 之前導部份處產生之RF信號（當雷射束從一結晶性區 至一非晶性區域時）之品質，係比在一記號的尾緣部份 生之RF信號（當雷射束從一非晶性區域移至一結晶性 要差，如第3圖中所示。 【發明内容】 鑑於先前技術之缺點，本發明的一目的在於提供 用於諸如CD-RW、DVD-RW及BD-RE之可重寫相變 位準 脈衝 之上 記號 間之 射掃 比前 液體 非冷 非晶 少非 8FP) 記號 域移 處產 區域） 一種 化光 1310180 碟的記錄方法，其係能增進記錄及播放特徵。 本發明的一目的在於提供一種用於可重寫相變化光碟 的記錄方法，其可防止結晶性材料由於來自多脈衝之熱， 而在預定記號（如記號長度4T或以上）之前導部份成長。 本發明又另一目的在於提供一種用於可重寫相變化光 碟的記錄方法，其減少或防止記號長度2 T與 3 T及記號長 度4 T以上的開始部份之不均等，該不均等係起因於在用 以形成記號長度4 T或以上之第一脈衝及多種脈衝間之間 隔的增加。 在本發明一具體實施例中，在用以形成預定記號（如記 號長度4T或以上）之寫入脈衝中的第一脈衝及多脈衝間之 間隔，係藉由將前導脈衝或所有多脈衝延遲而在預定極限 中增加。另一選擇是，在第一脈衝及多脈衝間之間隔的增 加，可藉由將用以形成長度記號2T或以上之第一脈衝及 最後脈衝向前移動，而在用以形成記號長度4T或以上之 寫入脈衝中的多脈衝保持不變。增加在用以形成記號長度 4T或以上之寫入脈衝中的第一脈衝及多脈衝間的間隔，可 防止結晶性材料由於來自多脈衝之熱，而在記號長度 4T 或以上的前導部份處成長。在此例中，多脈衝之寬度或位 準會增加以減少一頸狀之形成，其會由於在第一脈衝及多 脈衝間之間隔的增加而形成在該等記號之前導部份。 在另一具體實施例中，由於4T至8T記號長度之前導 部份因在用以形成記號長度4 T或以上之寫入脈衝中的第 一脈衝及多脈衝間的間隔之增加而移動，造成在記號長度 8 1310180 2 T與3 T及記號長度4 T以上的開始部份的不均等，可藉 由將用於記號長度3Τ之最後脈衝（3 LP)及用於記號長度4Τ 或以上的最後脈衝（4LP)向前.移動一預定時距t而避免。本 文中建議該預定時距不超過（3 Π 6；) T。 在又另一具體實施例中，在用以形成記號長度4T或 以上之寫入脈衝中的第一脈衝及多脈衝間之間隔係在一預 定極限中增加’而第一脈衝之開始位置、最後脈衝之開始 位置及寬度、及尾緣冷卻時間偏差係可個別地隨記號長度 調整。用以形成記號長度4T或以上之寫入脈衝係經調整， 以具有第一脈衝之相同開始位置、最後脈衝之相同開始位 置及寬度、相同及尾緣冷卻時間偏差。 【實施方式】 為充分了解本發明，現將參考附圖說明其較佳具體實 施例。 依據本發明用於相變化光碟的記錄方法可應用於包括 CD-RW、DVD-RW及BD_RE等之所有可重寫相變化光碟。 如第4圖中所不’ _利用本發明之光碟記錄器至少包含一 物鏡11、一雷射二極體 性® 1 2、一先束分先态丨3、_光感測 器及一 LD驅動器ι5。 1 5使用一參考時脈（ref_cl〇ck)產生對應於 LD驅動器 該NRZI L號之寫入脈衝，且提供該等脈衝至雷射二極體 因而重覆地形成對應於該NRZI信號（如2丁至之記 號及間距nT長度於相變化光碟之記錄層上。 1310180 現將描述其中多脈衝之位置偏移的一第一具體實施 例，其目的在於增進在4 T至8 T記號之前導部份處產生的 RF信號之品質。 為了增進已複製信號品質，由第一脈衝熔化的一記號 之前導部份需要快速地冷卻以成為非晶性。為此目的，接 著用於4T至8T記號之第一脈衝之多脈衝係第5a圖中所 示延遲。增加在用以形成記號4 T至8 T之第一脈衝及多脈 衝之開始間的間隔，可防止該等記號之前導部份受該等多 脈衝再加熱，且因此增加前導部份之冷卻速率，據以減少 在前導部份處成長之結晶性材料，如第5 b圖中所示。 如果該NRZI信號對應於記號長度4T至8T，LD驅動 器1 5會產生至少包含前導抹除功率持續時間（LE)、第一脈 衝（FP)、多脈衝（MP)、最後脈衝（LP)、及尾緣冷卻時間偏 差（TE)之寫入脈衝，藉由延遲該等多脈衝而增加在第一脈 衝及多重脈衝之開始間的間隔，其目的在於防止結晶性材 料由於來自多脈衝之熱，而在該等記號的前導部份處成 長。此外，所有或一些多脈衝之位準或寬度被調整，以補 償在具有高寫入功率之第一脈衝後的冷卻狀態，因而使由 於增加第一脈衝與多脈衝間之間隔而將形成在該等記號之 前導部份的一頸狀之形成最小化。 為形成一長度為4T之記號，一習知LD驅動器產生如 第6圖中所示之寫入脈衝Puls e_ A，其至少包含第一脈衝、 多脈衝及最後脈衝，其中所有脈衝之位準與寬度（W)係相 同，且脈衝間之間隔（即冷卻期間（C P))也是相同。在此例 10 1310180 中，該記號之前導部份會由來自多脈衝之熱再結晶，且 而減少。 為形成一長度為4 T之記號，利用本發明之L D驅動 15產生如第6圖中所示之寫入脈衝Pul se_B，其至少包 第一脈衝、多脈衝及最後脈衝，其中該等多脈衝被偏移 增加介於第一脈衝及該等多脈衝之開始間之間隔，且各 衝之寬度會增加（W’>W)。 結果，該冷卻時距係延伸（C P ’ > C P)，其防止結晶性 料由於來自多脈衝之熱，而在記號之前導部份成長。此夕| 該等多脈衝之寬度會增加以補償在具有高寫入功率之第 脈衝後的冷卻狀態，因而使在該等記號之前導部份的該 狀之形成最小化。 為形成一長度為4 T之記號，利用本發明之L D驅動 15產生如第6圖中所示之寫入脈衝Pulse —C，其至少包 第一脈衝、多脈衝及最後脈衝，其中用於該等多脈衝之 序未改變，但用於第一脈衝及最後脈衝之時序經調整， 增加第一脈衝及多脈衝之開始間的間隔，且各多脈衝之 度會增加（W’>W)。 為形成一長度為4 T之記號，利用本發明之L D驅動 15產生如第6圖中所示之寫入脈衝Pul se_D，其至少包 第一脈衝？多脈衝及最後脈衝，其中各該第一脈衝、多 衝、及最後脈衝之時序被調整以增加第一脈衝及多脈衝 開始間的間隔，且各多脈衝之寬度會增加（W’>W)。 結果，該冷卻期間係延伸（C P ’ > C P)，其防止結晶性 因 器 含 以 脈 材 ' ϊ 頸 器 含 時 以 寬 器 含 脈 之 材 11 1310180 料由於來自多脈衝之熱，而在記號的前導部份成長。此夕丨 該等多脈衝之寬度會增加，以補償在具有高寫入功率之 一脈衝後的冷卻狀態，因而使在該等記號之前導部份的 頸狀之形成最小化。 為形成一記號，利用本發明之L D驅動器1 5產生如 7圖中所示之寫入脈衝，其中介於第一脈衝及多脈衝之 始間的間隔係增加，各該等多脈衝之寬度未改變，且該 多脈衝之位準增加用於獲得較高之寫入功率，以補償在 有高寫入功率之第一脈衝後的冷卻狀態，因而使在該記 之前導部份的該頸狀之形成最小化。 介於用以形成4T至8T記號的第一脈衝及多脈衝之 始的間隔，可藉由如第8 (c)圖中所示只偏移該等多脈衝 之第一者，而非如第8(b)圖中所示延遲所有該等多脈衝 當用以形成記號長度4 T或以上之第一脈衝與多脈 之開始間的間隔增加，以增進在該記號之前導部份處的 製信號品質時，非晶性記號長度4 T或以上之範圍增加 方式，係使該記號之前導部份以與雷射光束行進方向相 之方向移動。此使得記號長度2 T及3 T比記號長度4 T 以上更短，此會因為一記號之開始點取決於其長度而得 較差之抖動特性。 現將描述用以解決上述問題之方法的一第二具體實 例，該方法係記號長度4T或以上之前導部份以與雷射 束行進方向相反之方向移動。 第9(a)圖示範依據第二具體實施例之寫入脈衝，而 第 該 第 開 等 具 號 開 中 〇 衝 複 之 反 或 到 施 光 第 12 1310180 9(b)圖示範由該寫入脈衝形成之記號的照片。 在第9(a)圖申所示之第二具體實施例中，^ 至8T記號之多脈衝（4MP至8MP)的開始被延域 多脈衝在其參考時脈之上升緣後開始，且用於 最後脈衝（3LP)及用於記號長度4T或以上的最 之上升緣係向前進一預定時距t(0<t<各3/16Τ) 後脈衝領先其參考時脈之上升緣。由該寫入脈 號長度2T、3T及4T的照片係如第9(b)圖中所 第9(a)圖中所示之寫入脈衝的波形係本發 性具體實施例，且因此本發明不受限於此。除 度4 T或以上外只用於3 T記號之最後脈衝的開 動一預定時距t(0<t<S 3/16T)，使得該最後脈 考時脈。此外，用於記號2T及3T之第一脈衝 前一預定時距，連同偏移在用以形成記號長度 或以上之寫入脈衝中的最後脈衝之開始。 上述寫入脈衝補償由於記號長度4T或以 份因在用以形成記號長度4T或以上的多脈衝 動，造成在記號長度2Τ與3Τ及記號長度4Τ 始位釁的不均等，因而造成較佳之抖動值。 第1 0至1 3圖比較習知記錄方法所應用及 具體實施例所應用的相變化光碟之特徵。該光 係2倍（正常速度的2倍）’且光碟記錄係在以 行。 /相變化光碟至少包含如第14圖中所示白 目以形成4Τ L，使得該等 3 Τ記號之 後脈衝（4 L Ρ) ，使得該最 衝形成之記 7f^ ° 明的一範例 用於記號長 始可向前移 衝領先該參 的開始可向 3T及/或4T 上之前導部 之延遲而移 或以上之開 本發明第二 碟旋轉速度 下條件下施 )許多層。在 13 1310180 一具有内徑1 5毫米、外徑12 0毫米、厚度1 _ 1毫米、軌距 0 · 3 2微米（包括島狀件及溝槽）之甜甜圈狀的聚碳酸鹽基材 2 1上，係堆疊一銀合金反射層2 2，一硫化辞-二氧化矽下 介電質保護層23、一下介面層24、一 Ge-Sb-Te合金記錄 層2 5、一上介面層2 6及一硫化辞-二氧化矽上介電質保護 層2 7。一厚度8 0微米之聚碳酸鹽覆蓋片2 8，係以2 0微米 厚度之UN樹脂黏合至該等多層。該光碟在使用前係藉由 一初始化設備加以初始化。在初始化後，該光碟之光學特 徵係使用一光碟驅動器及評估設備（如Pulstec之DD- 1 000) 加以評估。 施行記錄及播放之條件係如下： 通道位元時脈：1 3 2百萬赫（1 T = 7 · 5 7 5 7奈秒） 線性速度：1 0.5 6米/秒 碟片容量：23.3GB/邊 抖動量測設備：來自Υ 〇 k 〇 g a w a公司之T A 5 2 0 取樣：30,000樣本 讀取雷射功率：0.35毫瓦 底部雷射功率：〇. 5毫瓦 寫入雷射功率：5.2毫瓦 抹除雷射功率：1.9毫瓦 抖動指來自參考P L L時脈之前導及尾緣的偏差，係對 通道位元長度（CBL)正常化。至於抖動量測，記號及間距 長度2T至8T係重覆在一執上記錄N次，而後量測該抖動。 在第10至13圖中，（a)顯示藉由依據本發明之具體實 14 1310180 施例的寫入脈衝獲得之評估 獲得之評估& m如 、α果而（b)顯示藉由習知方法 線係當一® Α姑 顯不出二極限線。該10% —極限等化h + 之抖動極限，邢6.5%線係當 化态使用時之抖動極限。 第1〇圖顯示抖動相對於直接 習知等化器評估時，藉由第…之圖形。當使用 得的抖動…： 所示之習知寫入脈衝獲 起過10%極限，但依擔太 抖動維持在】〇〇/ 1 -冑本發明之寫入脈衝獲得的 付在i 〇 %極限下。 第11圖顯示抖動相對於寫 等化器評估時，士 " 》羊之圖形。當使用習知 、 果寫入功率係介於4.9毫瓦及5.7毫瓦 限，但2據本發明之寫入脈衝獲得的抖動值低於10%極 1。%之抖動：何寫入功率之習知寫入脈衝均無法獲得低於 相斟！ 12 & 13 81分别顯示抖動相對於切線料角及抖動 相對於彳呈南彳 白傾斜角。切線傾斜角容限(margin)(其係當使用 “評估時’獲得少於10%之抖動值的切線傾斜角 知 M依據本發明之寫入脈衝係-0.25度<0<〇.2度，但習 =入脈衝係_〇.丨度<θ<〇丨度。徑向傾斜角容限（其係當 =習知等化器評估時’獲得少力1〇%之抖動值的徑向傾 π範圍）以依據本發明之寫入脈衝係-〇 8度巧<〇·75产， :¾知之寫入脈衝係_〇75度<θ<〇6度。彼明顯的， 馬入脈衝獲得獲得較多的切線及徑向傾斜容限。 調整Π 15圖中所示’記號長度2T及3T之形狀可藉由 ° —脈衝、尾緣冷卻時間偏差及/或最後脈衝而控制。 15 1310180 同樣地，用以形成記號長度4 T或以上之第一脈衝、尾緣 冷卻時間偏差及/或最後脈衝可個別地或同時地調整。 有二種調整用於形成記號長度2Τ至8Τ之寫入脈衝， 以控制產生記號之可能方式。一者係相對於參考時序偏移 用以形成記號長度4Τ或以上之多脈衝的時序，而另一者 係偏移最後脈衝及/或第一脈衝之時序，且維持該多脈衝時 序不變。 在多脈衝之時序偏移方法（TSMP)中，存在於用以形成 記號長度4Τ或以上之第一脈衝（FP)及最後脈衝（LP)間的 多脈衝（ΜΡ)時序，係經調整以控制產生記號之形狀。例 如，在該等記號之前緣附近的非晶性材料範圍係保證將大 於一預定值。 如第16圖中所示，在多脈衝之時序偏移方法（TSMP) 中，用以形成記號長度2Τ至8Τ或9Τ之脈衝的寬度及時 序被設定，且尤其是該等多脈衝之時序係可變地調整。 第一脈衝之位置（dTtop)可表示為 dTtop = i*(T/16)， i = -1 6、-1 5、…、-1、0、1、2、…、1 5。i之值可視記號長 度而變化，且相同之i值係應用至所有用以形成記號長度 4T或以上之該等第一脈衝。 第一脈衝之寬度（Ttop)可表示為 Ttop=j*(T/16) + k*(l 奈秒），j、k = 0、…、15，Ttop22_5奈秒。而j與k之值可 視記號長度而變化，且相同之j與k值係應用至所有用以 形成記號長度4 T或以上之該等第一脈衝。 存在於第一脈衝及最後脈衝間之該等多脈衝之位置 16 1310180 (dTmp)可表示為 dTmp = m*(T/16)，m = -i6、-15、·.·、-1、0、 1、 2、…、1 5。相同之m值係應用至所有用以形成記號長 度4T或以上之該等多脈衝。 多脈衝之寬度（Tmp)可表示為Tmp =p*(T/l6) + q*(l奈 秒）’ p、q = 0、…、15，Tmpg 2 5奈秒。相同之p與q值 係應用至所有用以形成記號長度4 τ或以上之該等多脈衝。 最後脈衝之寬度（Tlp)可表示為Tlp = s*(T/16) + t*(i奈 秒），s、t = 〇、…、15 ’ Τ1ρ2 2·5奈秒。相同之3與t值係 應用至所有用以形成記號長度4T或以上之該等最後脈 衝’且不同值可應用至用以形成一記號長度3T之最後脈 衝。 用以在最後脈衝後形成一間距之尾緣冷卻時間偏差 (dTe)可表示為 dTe = u*(T/16)，u = -i6、-15、...、-1、〇、1、 2、 …、15°該u之值可視記號長度而變化，且相同之u值 係應用至所有用以形成記號長度4 T或以上之尾緣冷卻時 間偏差。 在上述方程式（如，dTtop及dTmp)’ 一正值表示相對 脈衝在該參考時脈之後，而一負值意指相對脈衝在該參考 時脈之前。 在最後脈衝之時序偏移方法（TSLP)中，用以形成記號 長度4T或以上的寫入脈衝中之最後脈衝（LP)的時序，係經 调整以控制產生記號之形狀，其方式係使得在該等記號之 則緣附近的非晶性材料之範圍將保證大於一預定值。 如第17圊中所示，在最後脈衝之時序偏移方法（TSLP) 17 1310180 度及時序被設定，且尤其是 整。 可表示為 dTtop=i*(T/16)， 、…、1 5。i之值可視記號長 用至所有用以形成記號長度 中，用以形成記號之脈衝的寬 最後脈衝之時序係經可變地調 第一脈衝之位置（dTtop) i=-16、 -15、…、-1、 0、 1、 2 度而變化，且相同之i值係應 4T或以上之該等第一脈衝。 第一脈衝之寬度（Ttop)可夹；* η J 表不為 Tt〇p=r(T/16) + k*(1 奈秒）’j、k = 0、…、15，Tt〇p>2 ς * ρ==ζ·5奈秒。而j與k之值可1310180 IX. Description of the Invention: [Technical Field] The present invention relates to a recording method for a phase change optical disc, and more particularly, but not limited to, a method for adjusting a laser write pulse of a phase change optical disc, Its purpose is to improve the quality of repeated records. [Prior Art] With the advent of multimedia generations including dynamic or static pictures, audio materials, and computer data in an integrated manner, the use of packaged media such as CDs and DVDs has rapidly increased and is expected to progress toward this path. New high-density optical discs such as Blu-ray Disc (BD) are rapidly evolving, and new disc-related products are expected to be available in the market in the near future. A package medium such as a CD, a DVD or a BD comprises at least a substrate, a recording layer and a protective layer. A read-only optical disc has pre-pits formed thereon to provide servo/location information and data, and has a reflective layer. A recordable or rewritable optical disc has a recordable dye or a phase change or magneto-optical recording layer, and a protective layer for protecting the recording layer and the pre-pits and a reflective layer. Recordable or rewritable discs can also be used as audio or video storage media and as computer data storage media. When a disc is used as a computer storage medium, the disc should be rewritten more than a video or an audio storage medium. For recording and playing back data, a laser beam emitted by a laser diode passes through an objective lens and reaches a reflective layer, a transparent protective layer (polycarbonate 5 1310180 substrate, which is used for a CD thickness of 1.2 mm). The DVD is 0.6 mm) and a recording layer, and the reflected laser beam is collected by a photodiode. In the case of a blue laser disc, a blue laser operating at a single wavelength of 405 nm and a high numerical aperture (NA) objective lens of 0.85 are used, and the protective layer having a thickness of 0.6 mm is composed of a thickness of 0.1 mm. The cover layer is replaced. The recording layer can be made amorphous or crystalline by phase change depending on the laser irradiation. The amorphous mark and the crystallographic pitch show a substantial difference in light reflection, and thus it can be used to represent binary data. Because of the accumulation of heat, a single laser pulse cannot form a perfectly shaped amorphous mark. For this reason, the multi pulses shown in Fig. 1 are usually used to form amorphous marks. Figure 1 illustrates the waveform of a conventional write pulse for a phase change optical disc. During recording, the laser output is modulated at three different power levels in accordance with a predetermined write strategy. The write power pw, which is the highest laser power, produces an amorphous state on the recording layer. The erase power P e (which is the intermediate power) melts the recording layer and converts it into a crystalline state. The bottom power Pb is the lowest laser power level. In the figure, FP, LE, MP, and LP represent the first pulse, the leading erase power duration, the multi-pulse or center pulse, and the laser pulse, respectively. TE represents the cooling time deviation from the trailing edge of the N R ZI end position (t r a i 1 i n g e d g e). For example, 3FT represents the first pulse of the 3T mark, 4MP to 8MP represents the multi-pulse of the 4T to 8Τ mark, 2ΤΕ represents the tail edge cooling time deviation of the 2Τ mark, and 4LP to 8LP represents the last pulse of the 4Τ to 8Τ mark. It is known that the eutectic based material for fabricating BD is grown to the main formula 6 1310180, and the shape of the amorphous region is sensitively varied with the width of the write pulse and the timing. Figure 2a illustrates a conventionally written waveform used to form a 2 T to 8 T mark, wherein the rising edge of each MP and LP is synchronized with a rising edge of a reference clock. Figure 2b illustrates a photograph of 2T to 8T formed by a write pulse. The boundary between the amorphous and crystalline regions at the trailing edge of a mark is easier to distinguish than at its leading portion. Therefore, when the mark is marked by the trace, the trailing edge portion shows a higher light reflection, and the resulting portion obtains a better jitter. During the writing phase, the recording layer is heated to the sleek point, and this is then rapidly cooled, allowing the atoms to solidify in an amorphous state. Except that the rate is high enough, crystalline materials grow from the boundary and reduce the area. The leading portion of the mark formed by the conventional write strategy shows the demagnetization region because the first pulse from the 4T to 8T mark (4FP to the subsequent multi-pulse (4M to 8M) reduces the cooling rate. As a result, The quality of the RF signal generated at the leading portion (when the laser beam is from a crystalline region to an amorphous region) is the RF signal generated at the trailing edge of a mark (when the laser beam Moving from an amorphous region to a crystallinity is poor, as shown in Fig. 3. SUMMARY OF THE INVENTION In view of the disadvantages of the prior art, it is an object of the present invention to provide for use in, for example, CD-RW, DVD-RW, and BD-RE rewritable phase change level pulse on the mark between the mark than the previous liquid non-cold amorphous less than 8FP) mark field shift production area) A method of recording the light 1310180 dish, its system can improve Record and play features. It is an object of the present invention to provide a recording method for a rewritable phase change optical disc which prevents a crystalline material from being partially grown before a predetermined mark (e.g., a mark length of 4T or more) due to heat from a plurality of pulses. . Still another object of the present invention is to provide a recording method for a rewritable phase change optical disc which reduces or prevents the unevenness of the start lengths of the symbol lengths 2 T and 3 T and the symbol length 4 T or more, the unequal system This is caused by an increase in the interval between the first pulse and the plurality of pulses for forming the mark length of 4 T or more. In one embodiment of the invention, the interval between the first pulse and the plurality of pulses in the write pulse used to form the predetermined mark (e.g., the mark length 4T or more) is delayed by the pilot pulse or all of the multiple pulses And increase in the predetermined limit. Alternatively, the increase in the interval between the first pulse and the multi-pulse can be used to form the mark length 4T by moving the first pulse and the last pulse for forming the length mark 2T or more forward. The multiple pulses in the above write pulse remain unchanged. Increasing the interval between the first pulse and the multi-pulse in the write pulse for forming the mark length 4T or more prevents the crystalline material from being at the leading portion of the mark length 4T or more due to heat from the multi-pulse growing up. In this case, the width or level of the multi-pulse is increased to reduce the formation of a neck which is formed in the leading portion of the mark due to the increase in the interval between the first pulse and the multi-pulse. In another embodiment, since the 4T to 8T mark length leading portion is moved due to an increase in the interval between the first pulse and the multi-pulse in the write pulse for forming the mark length 4 T or more, The unequality of the beginning of the mark length 8 1310180 2 T and 3 T and the mark length 4 T or more can be achieved by using the last pulse (3 LP) for the mark length 3 及 and the last for the mark length 4 或 or more. The pulse (4LP) is moved forward by a predetermined time interval t. It is recommended in this paper that the predetermined time interval does not exceed (3 Π 6;) T. In still another embodiment, the interval between the first pulse and the plurality of pulses in the write pulse for forming the mark length 4T or more is increased by a predetermined limit and the start position of the first pulse, and finally The start position and width of the pulse, and the trailing edge cooling time deviation can be individually adjusted with the length of the mark. The write pulses used to form the mark length 4T or more are adjusted to have the same start position of the first pulse, the same start position and width of the last pulse, and the same and trailing edge cooling time deviation. [Embodiment] In order to fully understand the present invention, a preferred embodiment thereof will now be described with reference to the accompanying drawings. The recording method for a phase change optical disc according to the present invention can be applied to all rewritable phase change optical discs including CD-RW, DVD-RW, and BD_RE. As shown in FIG. 4, the optical disc recorder using the present invention includes at least one objective lens 11, a laser diode property 1, 2, a first beam pre-state 丨3, a _photo sensor, and an LD. Drive ι5. 1 5 uses a reference clock (ref_cl〇ck) to generate a write pulse corresponding to the NRZI L number of the LD driver, and provides the pulses to the laser diode and thus repeatedly forms a signal corresponding to the NRZI (eg, 2 The mark of the Ding and the pitch nT are on the recording layer of the phase change optical disc. 1310180 A first embodiment in which the positional shift of the multi-pulse is described will be described, with the aim of enhancing the guide portion before the 4 T to 8 T mark. The quality of the RF signal generated at the portion. In order to improve the quality of the reproduced signal, a mark leading portion melted by the first pulse needs to be rapidly cooled to become amorphous. For this purpose, it is then used for the 4T to 8T mark. The multi-pulse of the first pulse is the delay shown in Figure 5a. The interval between the beginning of the first pulse and the multi-pulse used to form the marks 4 T to 8 T is prevented, and the leading portion of the marks is prevented from being affected by the Waiting for multiple pulses to reheat, and thus increasing the cooling rate of the leading portion, thereby reducing the growth of the crystalline material at the leading portion, as shown in Figure 5b. If the NRZI signal corresponds to the length of the mark 4T to 8T , LD drive 1 5 Generating a write pulse including at least a leading erase power duration (LE), a first pulse (FP), a multi-pulse (MP), a last pulse (LP), and a trailing edge cooling time deviation (TE) by delaying the The interval between the first pulse and the beginning of the multiple pulses is increased by a plurality of pulses, the purpose of which is to prevent the crystalline material from growing at the leading portion of the marks due to heat from the multi-pulse. Further, all or some of The level or width of the pulse is adjusted to compensate for the cooling state after the first pulse having a high write power, thereby causing the leading portion of the mark to be formed by increasing the interval between the first pulse and the multi-pulse To form a neck shape, a conventional LD driver produces a write pulse Pus e_A as shown in FIG. Pulse, in which the level of all pulses is the same as the width (W), and the interval between pulses (ie, the cooling period (CP)) is also the same. In this example 10 1310180, the leading part of the mark will be from multiple pulses. Thermal recrystallization, and reduced. To form a mark having a length of 4 T, the LD drive 15 of the present invention is used to generate the write pulse Pul se_B as shown in FIG. 6, which includes at least a first pulse, a multi pulse, and a last pulse, wherein the plurality of pulses are offset by an interval between the first pulse and the beginning of the plurality of pulses, and the width of each of the pulses is increased (W'>W). As a result, the cooling time is Extension (CP ' > CP), which prevents the crystalline material from growing due to the heat from multiple pulses, before the mark. The width of the multiple pulses will increase to compensate for the high write power. The cooling state after the first pulse thus minimizes the formation of the shape of the leading portion of the marks. To form a mark having a length of 4 T, the LD drive 15 of the present invention is used to generate a write pulse Pulse_C as shown in FIG. 6, which includes at least a first pulse, a multi-pulse and a last pulse, wherein The order of the multi-pulse is not changed, but the timings for the first pulse and the last pulse are adjusted to increase the interval between the start of the first pulse and the multi-pulse, and the degree of each pulse is increased (W'>W) . To form a mark having a length of 4 T, the L D driver 15 of the present invention is used to generate the write pulse Pul se_D as shown in Fig. 6, which includes at least the first pulse. a multi-pulse and a last pulse, wherein the timings of the first pulse, the multi-pulse, and the last pulse are adjusted to increase the interval between the start of the first pulse and the multi-pulse, and the width of each pulse increases (W'>W ). As a result, the cooling period is extended (CP ' > CP), which prevents the crystallizing agent from containing the pulse material ' ϊ 器 含 以 以 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 The leading part of the mark grows. At this time, the width of the plurality of pulses is increased to compensate for the cooling state after a pulse having a high writing power, thereby minimizing the formation of the neck portion of the leading portion before the markings. To form a mark, the LD driver 15 of the present invention generates a write pulse as shown in FIG. 7, wherein the interval between the first pulse and the beginning of the multi-pulse is increased, and the width of each of the multiple pulses is not Changing, and the level of the multi-pulse is increased to obtain a higher write power to compensate for the cooling state after the first pulse having a high write power, thereby causing the neck portion of the leading portion of the note The formation is minimized. The interval between the first pulse and the multi-pulse used to form the 4T to 8T mark can be offset only by the first one of the multiple pulses as shown in FIG. 8(c) instead of 8(b) delays the increase in the interval between the first pulse and the beginning of the multi-pulse used to form the mark length 4 T or more as shown in the figure to enhance the system at the leading portion of the mark. In the case of signal quality, the range of the amorphous mark length of 4 T or more is increased in such a manner that the leading portion of the mark moves in the direction opposite to the direction in which the laser beam travels. This makes the symbol lengths 2 T and 3 T shorter than the symbol length 4 T or more, which results in poor jitter characteristics because the start point of a mark depends on its length. A second specific embodiment of the method for solving the above problem will now be described. The method is such that the length of the mark 4T or more is moved in a direction opposite to the direction in which the laser beam travels. Figure 9(a) illustrates the write pulse according to the second embodiment, and the first open-ended equal-numbered open-cut 〇 〇 或 or to the illuminating 12 1310180 9(b) exemplifies the write A photo of the mark of the pulse formation. In the second embodiment illustrated in Figure 9(a), the beginning of the multi-pulse (4MP to 8MP) of the ^8 to 8T symbol is initiated by the extended multi-pulse after the rising edge of its reference clock, and The last pulse (3LP) and the most rising edge for the symbol length of 4T or more are advanced by a predetermined time interval t (0<t<3<3> each 3/16 Τ) and the pulse leads the rising edge of its reference clock. The waveform of the write pulse indicated by the write pulse number lengths 2T, 3T, and 4T as shown in the 9th (a) of FIG. 9(b) is a specific embodiment of the present invention, and thus The invention is not limited thereto. Except for the degree of 4 T or more, only the last pulse of the 3 T mark is activated for a predetermined time interval t (0<t<S 3/16T), so that the last pulse is the clock. In addition, the first predetermined time interval for the first pulse of the symbols 2T and 3T, together with the offset of the beginning of the last pulse in the write pulse used to form the mark length or above. The above-mentioned write pulse compensation causes unevenness in the mark lengths 2Τ and 3Τ and the mark length 4Τ position due to the symbol length 4T or the multi-pulse movement for forming the mark length 4T or more, thereby causing better jitter. value. Figures 10 to 13 compare the features of the phase change optical disc to which the conventional recording method is applied and which are applied to the specific embodiment. This light system is twice as large (twice the normal speed)' and the disc recording is in the line. The phase change optical disc contains at least a white eye as shown in Fig. 14 to form 4 Τ L such that the 3 Τ mark is followed by a pulse (4 L Ρ), so that an example of the most formed mark 7f^° is used for the mark The long start can be moved forward. The beginning of the reference can be moved to or above the 3T and/or 4T delays of the front guide. Many layers are applied under the conditions of the second disc rotation speed of the present invention. In 13 1310180 a donut-shaped polycarbonate substrate having an inner diameter of 15 mm, an outer diameter of 120 mm, a thickness of 1 mm, a gauge of 0 · 32 μm (including islands and grooves) 2 1 , stacked a silver alloy reflective layer 2 2, a sulfurized-cerium dioxide lower dielectric protective layer 23, a lower interface layer 24, a Ge-Sb-Te alloy recording layer 25, an upper interface layer 2 6 and a vulcanized word - erbium oxide on the dielectric protective layer 2 7 . A polycarbonate cover sheet 28 having a thickness of 80 μm is bonded to the plurality of layers of UN resin having a thickness of 20 μm. The disc is initialized by an initialization device prior to use. After initialization, the optical characteristics of the disc are evaluated using a disc drive and evaluation equipment (such as Pulstec's DD-1 000). The conditions for recording and playback are as follows: Channel bit clock: 1 3 2 megahertz (1 T = 7 · 5 7 5 7 nanoseconds) Linear speed: 1 0.5 6 m/s Disc capacity: 23.3 GB/ Edge jitter measurement equipment: TA 5 2 0 from 〇 〇k 〇gawa sampling: 30,000 samples read laser power: 0.35 mW bottom laser power: 〇. 5 mW write laser power: 5.2 mW Erasing laser power: 1.9 mW jitter refers to the deviation from the leading and trailing edges of the reference PLL clock, normalizing the channel bit length (CBL). As for the jitter measurement, the mark and the pitch length 2T to 8T are repeated for one recording N times, and then the jitter is measured. In Figs. 10 to 13, (a) shows an evaluation obtained by evaluation of a write pulse according to the embodiment of the present invention, as shown in Fig. 3, and a (b) shows by conventional means. The method line system does not show the second limit line when a Α Α 。. The 10% - limit equalizes the jitter limit of h + , and the Xing 6.5% line is the jitter limit when used. Figure 1 shows the graph of jitter with respect to the direct conventional equalizer evaluation. When using the jitter...: The conventional write pulse shown has a 10% limit, but the jitter is maintained at 〇〇/1 -胄 The write pulse obtained by the present invention is at the limit of i 〇% under. Figure 11 shows the jitter vs. write equalizer evaluation when the " sheep's graph. When using conventional, the write power is between 4.9 mW and 5.7 mW, but the jitter value obtained by the write pulse of the present invention is less than 10%. % jitter: The conventional write pulse of any write power cannot be obtained below! 12 & 13 81 shows the jitter and the tangent angle with respect to the tangent, respectively. Tangent tilt angle margin (which is when using the "evaluation" to obtain a tangent tilt angle of less than 10% of the jitter value. According to the present invention, the write pulse train is -0.25 degrees <0<0> , but Xi = into the pulse system _ 〇 丨 & θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ θ In the range of the tilting π), the writing pulse system according to the present invention is 度8 degreely < 〇·75,: 3⁄4, the writing pulse system _ 〇 75 degrees < θ < 〇 6 degrees. The pulse is obtained to obtain more tangential and radial tilt tolerances. Adjusting the shape of the 'mark lengths 2T and 3T shown in Fig. 15 can be controlled by °-pulse, trailing edge cooling time deviation and/or last pulse. 1310180 Similarly, the first pulse used to form the mark length 4 T or more, the trailing edge cooling time deviation and/or the last pulse can be adjusted individually or simultaneously. There are two adjustments for forming the mark length 2Τ to 8Τ The pulse is injected to control the possible way of generating the mark. One is used to form the mark length relative to the reference timing offset. Or the timing of the multi-pulse above, and the other is to shift the timing of the last pulse and/or the first pulse, and maintain the multi-pulse timing unchanged. In the multi-pulse timing offset method (TSMP), exists in The multi-pulse (ΜΡ) timing between the first pulse (FP) and the last pulse (LP) used to form a mark length of 4 Τ or more is adjusted to control the shape of the mark. For example, near the leading edge of the mark The range of amorphous material is guaranteed to be greater than a predetermined value. As shown in Figure 16, in the multi-pulse timing offset method (TSMP), the width and timing of the pulse length 2 Τ to 8 Τ or 9 记 are formed. The timing of the multi-pulse is set, and especially the timing of the multi-pulse is variably adjusted. The position of the first pulse (dTtop) can be expressed as dTtop = i*(T/16), i = -1 6, -1 5,... , -1, 0, 1, 2, ..., 15. The value of i varies depending on the length of the mark, and the same i value is applied to all of the first pulses used to form the mark length 4T or more. The width of the pulse (Ttop) can be expressed as Ttop=j*(T/16) + k*(l nanoseconds), j, k = 0,...,15 , Ttop22_5 nanoseconds, and the values of j and k vary depending on the length of the mark, and the same j and k values are applied to all of the first pulses used to form the mark length 4 T or more. The position of these multiple pulses between the last pulses 16 1310180 (dTmp) can be expressed as dTmp = m*(T/16), m = -i6, -15, ···, -1, 0, 1, 2,... 15. The same m value is applied to all of the multiple pulses used to form the symbol length 4T or more. The width of the multi-pulse (Tmp) can be expressed as Tmp = p*(T/l6) + q*(lNsec)' p, q = 0, ..., 15, Tmpg 2 5 nanoseconds. The same p and q values are applied to all of the multiple pulses used to form the symbol length 4 τ or more. The width of the last pulse (Tlp) can be expressed as Tlp = s*(T/16) + t*(i nanoseconds), s, t = 〇, ..., 15 Τ1ρ2 2·5 nanoseconds. The same 3 and t values are applied to all of the last pulses used to form the mark length 4T or more and the different values can be applied to the last pulse used to form a mark length 3T. The trailing edge cooling time deviation (dTe) used to form a pitch after the last pulse can be expressed as dTe = u*(T/16), u = -i6, -15, ..., -1, 〇, 1, 2, ..., 15° The value of u varies depending on the length of the mark, and the same value of u is applied to all trailing edge cooling time deviations used to form the mark length 4 T or more. In the above equations (e.g., dTtop and dTmp), a positive value indicates that the relative pulse is after the reference clock, and a negative value means that the relative pulse is before the reference clock. In the last pulse timing offset method (TSLP), the timing of the last pulse (LP) in the write pulse used to form the mark length 4T or more is adjusted to control the shape of the mark, in such a manner that The extent of the amorphous material near the edge of the marks will be greater than a predetermined value. As shown in the 17th, the timing shift method (TSLP) 17 1310180 degrees and timing of the last pulse are set, and especially the whole. It can be expressed as dTtop=i*(T/16), ,...,1 5. The value of i can be used as long as the length of the last pulse of the pulse used to form the mark is used to variably adjust the position of the first pulse (dTtop) i=-16, -15, ..., -1, 0, 1, 2 degrees vary, and the same i value is the first pulse of 4T or more. The width of the first pulse (Ttop) can be clamped; * η J is not Tt〇p=r(T/16) + k*(1 nanoseconds)'j, k = 0, ..., 15, Tt〇p> 2 ς * ρ==ζ·5 nanoseconds. And the value of j and k can
視記號長度而變化，且相同之i愈， J興k值係應用至所有用以 形成記號4T長度或以上之該等第^ 现氏。 多脈衝之寬度（Tmp)可表示a τ 不馬 Τϊ1ΐρ =P*(T/16) + q*(l 奈 秒），p、q = 0、…、1 5，Tmp g 2.5 夺孙.^ ^ 叙 估 不杪。相同之p與q值 係應用至所有用以形成長度記號竹或以上之該等多脈衝。 最後脈衝之位置（cmp)可表示為dTip=r*(T/i6)， 、-15、…' ^、〇、！、2、…、15。相同之Γ值係應Depending on the length of the mark, and the same i, the value of J is applied to all of the first lengths used to form the length of the mark 4T or above. The width of multiple pulses (Tmp) can represent a τ not Τϊ1ΐρ =P*(T/16) + q*(l nanoseconds), p, q = 0,...,1 5,Tmp g 2.5 夺孙.^ ^ The assessment is not wrong. The same p and q values are applied to all of the multiple pulses used to form the length mark bamboo or more. The position of the last pulse (cmp) can be expressed as dTip=r*(T/i6), , -15,...' ^, 〇, ! , 2, ..., 15. The same value
用至所有用以形成記號長度4Τ或以上之該等最後脈衝， 且不同值可應用至用以形成一記號長度3了之最後脈衝。。 最後脈衝之寬度（Tip)可表示為Tlp = s*(T/16) + t*(l奈 秒），s、t = 0、…' 15，Tip 2 2 · 5奈秒。相同之s與t值係 應用至所有用以形成記長度號4T或以上之該等最後脈 衝’且不同值可應用至用以形成一記號長度3T之最後脈 衝0 用以在最後脈衝後形成一間距之尾緣冷卻時間偏差 (dTe)可表示為 dTe = u*(T/16)，u = -16、-15、…、-1、0、1、 18 1310180 2…15該11之值可隨著γ之值變化，且相同之u值可 應用至所有用以形成記號長度4T或以上之尾緣冷卻時間 偏差。 依據本發明t TSMP方法應用於—可重寫藍光雷射光 碟（BD-RE)之條件，係與在第二具體實施例的實驗中類 似。因此在此只描述其差別。其使用相同之光碟、評估配 備及抖動量測設備。 資料係記錄在溝槽（雷射光束比島狀件先到達其）中， 即使用溝槽上記錄。該底部功率、寫人㈣、抹除功率分 别為〇·1毫瓦、5.2毫瓦、3·4毫瓦。雷射波長、通道位元 時脈、記錄線性速度及碟片容量分别為4〇8奈米、133百 萬赫（1Τ = 7·5757奈秒）、9·84求/秒及25gb/邊。該資料重 製通道位元時脈係66百萬赫且重製線性速度係4 92米/秒 米。資料係記錄在五個連續轨中，且抖動係在第三執上量 測。該直接重寫（DOW)抖動係依相同方式量測，但資料係 重覆地在五個連續軌上記錄，如N &，且在第三軌上之抖 動是在第N次記錄後量測。已記錄之資料至少包含2T至 8T記號及間距。 在dTmp係設定為〇之條件下，使直接重寫（^。…抖 動最小化之參數係如下列。對於2Τ記號，dTtop(2T) = 0.5 奈秒’ Ttop(2T) = 2_75奈秒及dTe(2T) = l奈秒。對於3T記 號 ’ dTtop(3T) = 0.75 奈秒，Ttop(3T) = 2.75 奈秒， Tlp(3T) = 3_25奈秒及dTe(2T) = 0.5奈秒。對於較長的記號， dTtop(2 4T) = 0.5 奈秒，Ttop(g 4T) = 3 奈秒，Tlp(g 4T) = 3.25 19 1310180 奈秒，dTe(2 4Τ)=1 奈秒，dTmp(2 4Τ) = 0(+1)奈秒且 Tmp(2 4T ) = 3.25 奈秒。 第18及19圖顯示當dTmp係設定為+ 1奈秒時抖動值 相對於寫入功率之圖式。+1奈秒之值表示用於4T至8T 記號之多脈衝在該參考時脈之上升緣後1奈秒開始。第1 8 圖顯示DOW(l)，即在1重寫後之抖動，而第1 9圖顯示 DOW( 10)，即在10次重寫後之抖動。 如所示，+1奈秒之dTmp獲得比〇奈秒之dTmp較低 之抖動值且更多的寫入功率容限。該dTmp之最佳值取決 於一光碟之記錄層的特徵。 與dTmp = 0比較’正dTmp指該等多脈衝係比第—脈 衝更靠近最後脈衝。在TSMP方法中之負dTmp的效果可 藉由在依據本發明之TSLP方法中設定dTmp成0且dT〇p、 dTlp及dTe為負值而達成，如第20圖中所示。 當dTmp = +l奈秒時，獲得相同效果之寫入脈衝參數儀 如下列。對於 2T 記號，dTtop(2T) = -〇.5 奈秒，Ttop(2T) = 2.75 奈秒及 dTe(2T) = 0 奈秒。對於 3T 記號，dTtop(3T) = -〇.25 奈秒，Ttop(3T) = 2.75 奈秒，Tlp(3T) = 3.25 奈秒，及 dTe(3T) = -0.5 奈秒。對於較長的記號，dTtop(2 4Τ) = -〇 5 奈秒，Ttop(g4T) = 3 奈秒 ’ Τ1Ρ(24Τ) = 3.25 奈秒，dTe(会 4T) = 0 奈秒，dTmpP 4T) = 〇 奈秒，及 Tmp(2 4T ) = 3.25 奈 秒。 依據本發明用於相變化光碟的記錄方法有效地防止該 等記號之前導部份被該等多脈衝再加熱，因而減少結晶性 20 1310180 材料在記號長度4T或以上之前導部份成長。 依據本發明用於相變化光碟的記錄方法有效地防止因 為多脈衝之偏移而增加抖動，以增進在記號長度4 Τ或以 上之前導部份處重製的信號品質。 依據本發明用於相變化光碟的記錄方法，可藉由調整 寫入脈衝之時序及寬度，增進相變化光碟中之記錄/重製特 徵。 雖然本發明已參考有限數量具體實施例加以揭示，熟 習此項技術人士（已受益於本揭露書者）將從其會瞭解各種 修改及變化。因此所有此修改及變化均落入本發明之精神 及範_中。 【圖式簡單說明】 本文包括之附圖提供對本發明的進一步瞭解，示範本 發明之較佳具體實施例，且連同說明書用以解說本發明之 原理。 第1圖示範一用於相變化光碟之習知寫入脈衝的波形； 第2圖示範一用以產生2 Τ至8 Τ記號之習知寫入脈衝的波 形，及一由該寫入脈衝形成之2 Τ至8 Τ記號的照片； 第3圖示範其中雷射束掃描相變化光碟中的一間距及跟著 該間距的一記號之實例； 第4圖示範用以調整相變化光碟之一寫入脈衝的設備之方 塊圖； 第5圖示範一用以產生4 Τ至8 Τ記號之寫入脈衝的波形， 21 1310180 其中多脈衝之位置係依據本發明一具體實施例而偏 移，及一由該寫入脈衝形成之2 T至8 T記號的照片； 第6圖示範依據本發明之寫入脈衝的波形，其中第一脈衝 與該等多脈衝之開始的間隔已增加，及由該等寫入 脈衝形成之記號的照片； 第7圖示範依據本發明之寫入脈衝的波形，其中第一脈衝 及該等多脈衝之開始的間隔已增加，且等該多脈衝 之位準已增加； 第8圖示範依據本發明之寫入脈衝的波形，其中第一脈衝 及該等多脈衝之開始的間隔係藉由只偏移該等多脈 衝之第一者而增加； 第9圖示範依據本發明之寫入脈衝的波形，其中用以產生 記號4 T或以上長度之多脈衝係延遲，且用於記號 3T或以上長度之最後脈衝係提前，及一由該等寫入 脈衝形成之記號的照片； 第10圖示範藉由習知寫入脈衝及藉由依據本發明之寫入 脈衝獲得的抖動對直接重寫數目之圖形； 第 Π 圖示範藉由習知寫入脈衝及藉由依據本發明之寫入 脈衝獲得的抖動對寫入功率之圖形， 第1 2圖示範藉由習知寫入脈衝及藉由依據本發明之寫入 脈衝獲得的抖動對切線傾斜之圖形； 第1 3圖示範藉由習知寫入脈衝及藉由依據本發明之寫入 脈衝獲得的抖動對徑向傾斜之圖形； 第1 4圖示範一相變化光碟之剖面圖； 22 1310180 第1 5圖示範本發明一具體實施例，其中用以形成各記號之 第一脈衝、多脈衝、最後脈衝及/或尾緣冷卻時間偏 差之位置、寬度及位準係經調整； 第1 6圖示範依據本發明之TSMP方法，其中用以形成記號 2T至9T長度之脈衝的寬度及位置係經調整； 第1 7圖示範依據本發明之T S LP方法，其中用以形成記號 2 T至9 T長度之脈衝的寬度及位置係經調整；All of the last pulses used to form a mark length of 4 Τ or more are used, and different values can be applied to the last pulse used to form a mark length of 3. . The width of the last pulse (Tip) can be expressed as Tlp = s*(T/16) + t*(lNsec), s, t = 0, ...' 15, Tip 2 2 · 5 nanoseconds. The same s and t values are applied to all of the last pulses used to form the length number 4T or above and the different values can be applied to the last pulse 0 used to form a mark length 3T for forming a post after the last pulse. The trailing edge cooling time deviation (dTe) of the pitch can be expressed as dTe = u*(T/16), u = -16, -15, ..., -1, 0, 1, 18 1310180 2...15 The value of 11 can be As the value of gamma changes, the same value of u can be applied to all trailing edge cooling time deviations used to form the mark length 4T or more. The conditions under which the t TSMP method is applied to the rewritable Blu-ray laser disc (BD-RE) according to the present invention are similar to those in the experiment of the second embodiment. Therefore only the differences will be described here. It uses the same optical disc, evaluation equipment and jitter measurement equipment. The data is recorded in the trench (the laser beam reaches it first than the island), ie it is recorded on the trench. The bottom power, the write (4), and the erase power are respectively 〇·1 mW, 5.2 mW, and 3.4 mW. The laser wavelength, channel bit clock, recording linear velocity, and disc capacity are 4〇8 nm, 133 million Hz (1Τ = 7.5757 nnn), 9.84 sec/sec, and 25 gb/side, respectively. This data reproduces the channel bit clock system at 66 MHz and the re-linear velocity system is 4 92 m/s. The data is recorded in five consecutive tracks and the jitter is measured on the third. The direct overwrite (DOW) jitter is measured in the same way, but the data is repeatedly recorded on five consecutive tracks, such as N & and the jitter on the third track is after the Nth record. Measurement. The recorded data contains at least 2T to 8T marks and spacing. Under the condition that dTmp is set to 〇, the parameter that minimizes direct rewriting (^.... jitter is as follows. For 2Τ mark, dTtop(2T) = 0.5 nanoseconds 'Ttop(2T) = 2_75 nanoseconds and dTe (2T) = l nanoseconds. For the 3T mark 'dTtop(3T) = 0.75 nanoseconds, Ttop(3T) = 2.75 nanoseconds, Tlp(3T) = 3_25 nanoseconds and dTe(2T) = 0.5 nanoseconds. Long mark, dTtop(2 4T) = 0.5 nanoseconds, Ttop(g 4T) = 3 nanoseconds, Tlp(g 4T) = 3.25 19 1310180 nanoseconds, dTe(2 4Τ)=1 nanoseconds, dTmp(2 4Τ ) = 0 (+1) nanoseconds and Tmp(2 4T ) = 3.25 nanoseconds. Figures 18 and 19 show the plot of jitter value versus write power when dTmp is set to + 1 nanosecond. The value of seconds indicates that the multi-pulse for the 4T to 8T mark starts at 1 nanosecond after the rising edge of the reference clock. Figure 18 shows DOW(l), which is the jitter after 1 rewriting, and the 19th The figure shows DOW(10), which is the jitter after 10 rewrites. As shown, the dTmp of +1 nanoseconds obtains a lower jitter value than the dTmp of the nanosecond and has more write power tolerance. The optimum value of dTmp depends on the characteristics of the recording layer of a disc. Compare with dTmp = 0 'positive d Tmp means that the multi-pulse is closer to the last pulse than the first pulse. The effect of the negative dTmp in the TSMP method can be set by setting dTmp to 0 and dT〇p, dTlp and dTe in the TSLP method according to the present invention. The value is achieved as shown in Fig. 20. When dTmp = +l nanoseconds, the write pulse parameter meter that achieves the same effect is as follows. For 2T mark, dTtop(2T) = -〇.5 nanoseconds, Ttop (2T) = 2.75 nanoseconds and dTe(2T) = 0 nanoseconds. For 3T marks, dTtop(3T) = -〇.25 nanoseconds, Ttop(3T) = 2.75 nanoseconds, Tlp(3T) = 3.25 nanoseconds , and dTe(3T) = -0.5 nanoseconds. For longer marks, dTtop(2 4Τ) = -〇5 nanoseconds, Ttop(g4T) = 3 nanoseconds 'Τ1Ρ(24Τ) = 3.25 nanoseconds, dTe( Will 4T) = 0 nanoseconds, dTmpP 4T) = 〇 nanoseconds, and Tmp(2 4T ) = 3.25 nanoseconds. The recording method for a phase change optical disc according to the present invention effectively prevents the front portion of the mark from being reheated by the plurality of pulses, thereby reducing the crystallinity. The material of the 13 1310180 material is partially grown before the mark length of 4T or more. The recording method for a phase change optical disc according to the present invention effectively prevents the jitter from being increased due to the shift of the multi-pulse to enhance the signal quality reproduced at the leading portion of the mark length of 4 Τ or more. According to the recording method for a phase change optical disc of the present invention, the recording/reproduction characteristics in the phase change optical disc can be enhanced by adjusting the timing and width of the write pulse. While the invention has been described with respect to the embodiments of the embodiments of the invention Therefore, all such modifications and variations are intended to fall within the spirit and scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in FIG Figure 1 illustrates a waveform of a conventional write pulse for a phase change optical disc; Figure 2 illustrates a waveform of a conventional write pulse for generating a 2 Τ to 8 Τ mark, and a waveform formed by the write pulse Photographs of 2 Τ to 8 Τ marks; Figure 3 illustrates an example of a spacing in a laser beam scanning phase change optical disc and a mark following the spacing; Figure 4 illustrates an example of adjusting one of the phase change optical discs to be written Block diagram of a pulsed device; Figure 5 illustrates a waveform for generating a write pulse of 4 Τ to 8 Τ, 21 1310180 where the position of the multi-pulse is offset according to an embodiment of the present invention, and The write pulse forms a photograph of the 2 T to 8 T mark; FIG. 6 illustrates the waveform of the write pulse according to the present invention, wherein the interval between the first pulse and the beginning of the multiple pulses has increased, and is written by the write a photograph of the mark formed by the pulse; FIG. 7 illustrates a waveform of the write pulse according to the present invention, wherein the interval between the start of the first pulse and the plurality of pulses has increased, and the level of the multi-pulse has increased; Figure 8 illustrates the writing in accordance with the present invention a waveform of the rush, wherein the interval between the first pulse and the beginning of the plurality of pulses is increased by shifting only the first one of the plurality of pulses; FIG. 9 illustrates the waveform of the write pulse according to the present invention, wherein To generate a multi-pulse delay of the symbol 4 T or more, and to use the last pulse of the length of 3T or more to advance, and a photo of the mark formed by the write pulses; FIG. 10 illustrates by conventional means The write pulse and the pattern of the jitter pair obtained by the write pulse according to the present invention directly overwrite the number; the figure illustrates the jitter write pair obtained by the conventional write pulse and by the write pulse according to the present invention The graph of the power input, FIG. 2 is a graph illustrating the slanting of the tangential line by the conventional write pulse and the write pulse according to the present invention; FIG. 3 is a diagram illustrating the conventional write pulse and borrowing A graph of jitter versus radial tilt obtained from a write pulse in accordance with the present invention; Figure 14 illustrates a cross-sectional view of a phase change optical disc; 22 1310180 Figure 15 illustrates an embodiment of the present invention in which Mark The position, width, and level of the deviation of one pulse, multiple pulses, last pulse, and/or trailing edge cooling time are adjusted; Figure 16 illustrates a TSMP method in accordance with the present invention in which pulses of length 2T to 9T are formed. The width and position are adjusted; Figure 17 illustrates a TS LP method in accordance with the present invention in which the width and position of the pulses used to form the length of the symbols 2 T to 9 T are adjusted;
第18及19圖在依據本發明之TSMP方法中的多脈衝之不 同位置的抖動對寫入功率之圖形； 第20圖示範依據本發明之TSMP方法及TSLP方法的相等。 在不同圖式中由相同數字提及之本發明的特徵、元件 及特點，表示依據一或多數之具體實施例的相同、等效或 類似之特徵、元件、或特點。Figures 18 and 19 are graphs of jitter versus write power at different locations of multiple pulses in a TSMP method in accordance with the present invention; Figure 20 illustrates the equalization of the TSMP method and the TSLP method in accordance with the present invention. The features, elements, and characteristics of the present invention, which are referred to in the different figures, are the same, equivalent, or similar features, elements, or characteristics in accordance with one or more specific embodiments.
【主要元件代表符號說明】 11 物鏡 12 雷射二極體 13 分光器 14 光感測器 15 LD驅動器 2 1 基材 22 銀合金反射層 23 硫化辞-二氧化矽下介電質保護層 24 一下介面層 25 Ge-Sb-Te合金記錄層 26 一上介面層 27 上介電質保護 28 聚碳酸鹽覆蓋片 23[Main component representative symbol description] 11 Objective lens 12 Laser diode 13 Beam splitter 14 Photo sensor 15 LD driver 2 1 Substrate 22 Silver alloy reflective layer 23 Vulcanized word - Dioxide under dielectric protective layer 24 Interfacial layer 25 Ge-Sb-Te alloy recording layer 26 Upper dielectric layer 27 Upper dielectric protection 28 Polycarbonate cover sheet 23