201118418 六、發明說明： t考务明所属拓L称T領起^ 3 本發明係關於一種可特別使用在眼用雷射外科裳置中 的光學成像系統’而且其亦可使用在用於其它加工任務(例 如，光電伏特計或工業材料加工）的雷射系統中。 I：先前技術3 特別是，本發明提供一種光學成像系統，其允許傳送 通過該成像系統的雷射束之焦點在z方向中快速位移；根據 習知的命名法，Z方向代表束路徑的方向（光束傳播方向）。 然後，X或y方向經了解為在與z方向正交之平面中的任何方 向。在此平面中，為了掃描欲藉由雷射束加工的材料區域 之目的，習知上藉由掃瞄器來進行雷射束的移動；該欲加 工的材料可為活的或死的材料。 將發射出在飛秒範圍内的短脈衝輻射之雷射系統使用 在眼睛外科中，尤其是在角膜中（而且亦在人類水晶體中） 製得組織内切口。於此實例中所使用之效應為光學的重大 發現其導致曝光組織所謂的光爆破(ph〇t〇diSrUpti〇n)。此 光爆破之產生需要比較強的雷射束聚焦，其藉由讓使用於 聚焦的聚焦絲儀n具有相應大的光圈達成。在已知的眼 科學fs雷射系統巾，該聚焦光學儀器通常藉由所謂的f-θ物 鏡形成’其紐當掃㈣雷射束時可平面場成像及可避免 在2方向中不希望得到的束焦點位移。 fs雷射系統在眼科學(例如，用於lasik應用）中具有重 要位置。LASIK代表雷射原位屈光性角膜重塑術(1_比 201118418 situ keratomileusis)及指為用來修正視覺缺陷的角膜處理技 術，其在角膜表面上切開一仍然部分連接至角膜組織之所 謂的“瓣”’然後將此瓣折Φ至旁邊，及在折疊該瓣後，根 據患者特定的切除外形，以短波雷射光(例如，在193奈米 處發射的準分子雷射）來切除曝露出的基質組織。 為了產生S亥瓣切割，已知藉由壓平板來平整化欲處理 的眼睛及在角膜内部於平面上二維地導引該束焦點。由於 由f-θ物鏡提供平面場成像，其不需要焦點之任何2位移。若 想要從該基質從事該瓣的邊緣切割時，可僅在該瓣的邊緣 區域中需要於Z方向中位移焦點位置。 已經於先述技藝中對在2方向中的焦點位移提出多種 解決方案。WO 03/032803 A2提出在z軸方向（即，沿著束路 徑）上整體位移該聚焦物鏡。其變型為將該聚焦物鏡裝配成 變焦物鏡。但是，二方法皆具有必需非常精確地進行聚焦 物鏡之機械位移或變焦設定的缺點，因為其將會以丨：i轉 換成焦點位置調整。對想要在雷射束的連續脈衝間位移焦 點數微米來說，因此，將需要聚焦物鏡或物鏡的變焦鏡頭 在相同距離上相應地快速機械位移。習知的機械傳動設備 不合適於此。 另一種解決方案顯現在DE 10 2005 013 949 A1中。在 其中的雷射系統具有—二鏡片擴展光學儀器（擴束器，設計 如為望遠鏡）、一下游掃瞄器及一在該掃瞄器後的聚焦鏡。 该擴展光學儀器的入口鏡片（裝配如為凹透鏡)可藉由線性 傳動設備在束方向中（即，在z方向中）位移。此入口鏡片的 201118418 位移修改從擴展光學儀器所射出的雷射束之發散。若聚焦 鏡(f-θ物鏡）的位置仍然固定時，因此，焦點位置在Z方向中 移動。 此對聚焦光學儀器的Z位移之解決方案的優點在於較 好的再現能力及較高的位移準確性，因為該光學成像系統 將擴束器的入口鏡片之位移移動轉換成焦點位置的位移移 動（其減少例如因子10)。但是，該入口鏡片可達成的調整速 率受限於轉換成焦點平面的束焦點位移速率。對三維切割 來說(如例如角膜透鏡體摘出所需要），一般公認根據DE 10 2005 0139 49 A1的焦點調整方法比顯現在w〇 03/032803 A2中的方法更快，此簡單地因為在調整擴束器的入口鏡片 之實例中，欲移動的主體遠少於在調整整體聚焦光學儀器 的實例中者。同時存在的是’聚焦光學儀器可容易地重達 數公斤，但是其仍然必需沒有振動地移動。另一方面，擴 束器的入口鏡片可具有比較小的光圈及相應地小及重量 輕。然而，當想要以雷射（其足夠快速地重複)在可接受地短 的時間内製得角膜内透鏡體切割或另一種三維切口時，習 知的線性傳動設備無法滿足需求。可使用習知的線性傳動 設備，以例如在約1至3毫米/秒間的調整速率來可信賴、無 傾斜地引導擴束器的入口鏡片’然而亦可以可容忍的費用 達成最高約5毫米/秒的入口鏡片之機械引導。但是，對透 鏡體切割來說，當使用在二至三位數的千赫範圍内或甚至 較快重複的fs雷射與相同的z焦點調整原理時，將需要至少 10毫米/秒或更高的入口鏡片調整速率，此無法以商業可購 201118418 得的線性傳動設備系統達成，至少不是能滿足調整準確性 及引導精確度的需求之那些系統。 除了擴束器的入口鏡片之線性移位能力外，de川 2005 013 949 A1提出將二片凹面鏡放置在雷射與掃目苗器間 之束路徑中，雷射束（因此其焦點位置）在2方向中的發散可 藉由改變凹面鏡之相互間距而變化。於此再次，可比較的 限制存在於機械的調整速度。 L發明内容3 本發明的目的之一為提供一種更合適於在材料加工中 及特別在眼科學中的三維焦點引導之光學成像系統。 為了達成此目標，本發明提供一種具有至少一片可變 形的鏡子及一調整與控制配置的光學成像系統，其中該配 置連結至該鏡子及藉由鏡子之變形（特別根據預定的焦點 位移曲線)調適，以在光束傳播方向中位移該成像系統的影 像邊焦點。 該可變形的鏡子及其在雷射系統中的用途本身已知。 例如’就這一點而言，可參考S.綿（Menn)，P.比爾登 (Bierden) ’ 在雷射 + 光子學(photonik) 4/2007，第 18-22頁中 之“Spieglein ’ Spieglein...，Technologische Fortschitte und Anwendungen verformbarer Mikrospiegel”[鏡子，鏡子…， 可變形的微鏡之技術性發展及應用]。特別是，根據在此論 文中的資訊’該可變形的鏡子可分成五種不同的基本變 型，換句話說，可變形的MEMS鏡子(MEMS :微機電系統）、 壓電性可變形的鏡子、可變形的薄膜鏡子、雙態可變形的 6 201118418 鏡子及鐵磁性可變形的鏡子。本發明不想要受限於這些不 -⑽子型式的特_子。原則上，可在純系統的望遠鏡 内使用任何能讓入射的雷射束之波前具有想要的修改之可 變形的鏡子。藉由仙雷射的束引導+使用可變形（調適） 的鏡子’可達成更快的束焦點之2位移（與習知的機械線性 調整系統比較，例如m個級數大小卜 可調適的鏡子之-個已知的應用領域為例如在天文觀 察中。於此’受擾礼的波前藉由可調適的鏡子轉換成平面 波前’以便改良所接收由大氣干擾而變形的光之影像品 質。與此比較，本發明不企圖藉由可變形的鏡子之相應變 形來消除不希望得到的波前魏。反而，本發明旨在藉由 纟適地膽可μ的鏡子來變形人射在鏡子上的光束之波 前，以便該成像系統（因此該束焦點）之影像邊焦點以想要的 方式在Ζ方向上位移。較佳的是，調適該調整與控制配置， 以將該鏡子調整至可將基本上平面入射波轉換成具有基本 上一致的彎曲波前之反射波形狀，其波前曲率的強度依在 光束傳播方向中之想要的焦點位置而定。對在聚焦處高束 品質來說，想要波前曲率的一致性。因此，本發明基本上 逆轉可δ周適的鏡子用來改良波前的可平面性之習知用途， 及從大約平面波則蓄意地產生一明確、持續可變的波前曲 率。所產生的波前曲率可意謂著發散增加或減少，以便該 束焦點在一個方向中位移或其它從預定的中立位置 position)起始。 在一個具體貫例中，可在光束傳播方向中，將該鏡子 7 201118418 安排在望遠鏡前。另一方面，在另一個具體實例中可在 光束傳播方向中，將其安排在望遠鏡後，但是在具有至少 單一鏡片的聚焦光學儀器前，及在掃瞄器前較佳。再者， 根據更另一個具體實例，可理解的是，由二片鏡子建構出 束擴展光學儀器及將鏡子之一安裝成可調適可變形的鏡 子，藉此可將想要的發散引進該束中。 由本發明促進，在Z方向上快速焦點位移對使用在那些 眼科學應用中特別具吸引力（其以快速重複聚焦的fs雷射轄 射操作及需要快速三維切Π引導—段短的處理時間）。因 此，本發明的另-個觀點提供—種用於眼用f㈣科的裝 置，其具有脈衝的飛秒f射束來源、擴展雷射束的束擴展 光學儀器、在該擴展光學儀器下游用來在與該束路徑垂直 的平面中偏轉該雷射束之掃晦器、及在該掃㈣下游用來 聚焦該雷射束之聚焦光學儀器，其中該裝置具卜可_ 的鏡子(其錢在光束傳射向中，於雷射㈣與聚焦光學 儀益間)及-程式控制之調整與控制配 及根據欲在患者眼睛中產生及藉由控制程式纽之預定: 切割外形調適’以變形該鏡子而在束路財向中位移束隹 點）。可調適該調整與控制配置以控制該 _ 束的束焦點可在束路徑方向中位移至少心= 150微米較佳，至少2〇〇微米更佳 可從本發明的快速三維切 個可能的應 201118418 用為角膜透鏡體摘出，其中從肖膜基f切出—大約透鏡形 體積單元來修正角臈折射。對此來說，精確及快速地三維 定位fs雷射脈衝的焦點重要。此掃瞄器在x y方向中之相應 快速的操作沒有問題。例如，根據電流計原理操作的習知 鏡子掃描器能夠容易地保證所需要的偏轉，甚至在百萬赫 茲範圍内的脈衝重複時。可藉由使用可變形的鏡子，容易 地在Z方向中，於數毫秒或至少數十毫秒内，在高範圍（二 位數至三位數微米）内偏移束焦點。對角膜透鏡體摘出來 說，例如，其允許在數分鐘(例如，2_4分鐘）或甚至在少於i 分鐘(依透鏡體的尺寸而定）内進行整體透鏡體切，其將由 患者在此操作下所遭受到的不舒服度限制在儘可能短的時 間内。再者，本發明打開沒有如先前習知般使用準分子雷 射來折射性修正眼睛的機會，因為在透鏡體摘出期間，束 焦點之z位置的高精確度及再現能力允許束引導與欲修正 的視覺缺陷準確地相配。 圖式簡單說明 本發明將藉由所附加的圖形之輔助更詳細地描述在下 列，其中： 第1圖圖式地顯示出人類眼睛的m含角膜之戴 面圖，於其中指示出角膜透鏡體切割； 第2圖圖式地顯示出將根據本發明之裝置用於眼用雷 射外科的實施例； 第3圖顯示出此眼用雷射外科裝置的第一種變化；及 第4圖顯示出另一種變化。 201118418 【實施方式3 首先，參照第1圖。其以截面表示顯示出人類眼睛的角 膜（由10表示）。眼睛的光學軸(觀看軸）由點及破折號指示出 且由12表示。角膜10具有前表面14及背表面16。人類眼睛 的厚度d之典型範圍約500微米，當然可依人而異而向上或 向下變化。眼睛的鞏膜及緣在第1圖中由18指示出，及緣的 邊緣由20表示。 在第1圖中，欲藉由聚焦的fs雷射輻射處理切開之角膜 内或更精確地基質内透鏡體22亦由破折號指示出，其隨後 經由欲側面引進角膜10中之開口操作地摘出。此開口亦可 藉由雷射切割產生。飛秒透鏡體摘出允許修正視覺缺陷（例 如，近視及近視性散光）。透鏡體22習知地藉由基本上平坦 後端切割24及彎曲前端切割26產生。透鏡體直徑（在第1圖 中由a表示）範圍例如在約6至8毫米之間，同時典型的透鏡 體厚度（由b表示）為例如約80-100微米。隨著這些透鏡體的 厚度值，可修正約-5 dpt至-6 dpt的視覺缺陷。要瞭解透鏡 體直徑及透鏡體厚度二者可根據欲修正的視覺缺陷強度而 變化。但是，在任何事件中，該透鏡體厚度將經常為數十 微米，其與大約平坦透鏡體的下邊（由後端透鏡體切割24定 義）相關連，意謂著在雷射束於透鏡體頂端（即，透鏡體22 具有最大的厚度處)上之線掃描中，雷射束的束焦點必需在 光束傳播方向執行與透鏡體厚度相應的偏移。 現在，亦參照第2圖。在其中顯示出的雷射裝置包括飛 秒雷射來源28，其例如由纖維雷射形成，其產生具有脈衝 10 201118418 週期在飛秒範圍内及脈衝重複速率在高（二位數至三位數) 千赫範圍内（或甚至在百萬赫茲範圍内較佳）之脈衝雷射輻 射30。所產生的雷射束藉由擴展光學儀器32擴展。在光束 傳播方向中，於擴展光學儀器32前有一有效可變形的鏡子 34，其變形狀態可藉由通常由36表示之引動器配置（其依次 由程式控制的控制單元38驅動）調整。該鏡子34具有多樣性 可藉由引動器配置36調整的各別鏡子面，及該引動器配置 36可例如具有壓電式驅動元件、MEMS驅動元件、驅 動元件(DMD :數位微鏡裝置）或LCD驅動元件(LCD :液晶 裝置）。 ' 再者，在所顯示出的典型實例中，處在該鏡子料前者 為被動偏轉鏡子40，但是其在波前特徵(因此雷射束3〇之發 散)上無效應或至少無實質上效應。 由擴展光學儀韻擴展㈣射束(及由42表㈤隨後旅 經至掃猫祕，其目的為在與光束傳射向㈣向；參昭 同樣在第2圖中指示出的座標系統)正交的xy平面中 射束42 ’因此在欲處理的眼睛區域上掃描該雷射束。在所 顯示出的典型實例中，該掃猫器根據電流計原理作用及藉 由二片可傾斜的偏轉鏡子46,48(其可由控财元侧綱 成。要瞭解同樣可根據其它原理來操作掃描器(例如，藉由 可合適地控制的晶體掃描）。 掃猫器44接著聚焦物鏡50(特別是fe 聚焦到焦點位置52上）。在所顯示出的典型實財 獅安裝有二片鏡片54,56。要瞭解物鏡啊容易地裝配有 201118418 任何其它想要的鏡片數目。聚焦物鏡(如f-θ物鏡）的具體實 例導致平面場成像，其中焦點位置50總是位於與z方向正交 的平面處而與雷射束之偏轉角度無關。 在所顯示出的典型實例中，該束擴展光學儀器32由具 有負折射功率（凹透鏡）的入口鏡片58與具有正折射功率 (會聚透鏡）的出口鏡片60之伽利略（Galilean)望遠鏡形 成。再者，具有二片凸透鏡之開普勒（Keppler)版望遠鏡可 能。 根據一個典型的具體實例，入射在鏡子34上的雷射束 3〇具有一基本上平面波前，對焦點位置52的預定參考位置 (中立位置）來說，其從鏡子34中反射而基本上沒有彎曲效 應，因此基本上保存其平面波前。對焦點位置52從此中立 位置在z方向上位移來說，控制單元38可經由中間引動器配 置36來調整鏡子34，以便該入射雷射束3〇的平面波前轉換 成基本上一致的彎曲波前。依波前曲率的本質而定，此可 讓該雷射束發散或會聚。此在束發散上的改變導致焦點位 置52在z方向中位移，而其它方面擴展光學儀器^固定地配 置·同樣未移動聚焦物鏡50。 控制單元38根據欲在眼睛中產生的切割曲線來控制引 動器配置36，因此鏡子34的變形狀態。用於控制單元38的 相應控制程式貯存在記憶體（無詳細地顯示出）中。切割曲線 或控制程式詳細指出該光學成像系統的焦點對在x · y平面 中的不同位置於2方向中位移之方法，及在本發明的觀念 中，此程度為典型的焦點位移曲線。可驅動及引動合適於 12 201118418 鏡子34的引動器之精確度及速度使得可在數十毫秒或甚至 數毫秒内達成束焦點在數十微米範圍内z偏移。因此，可在 以fs雷射系統有效及快速地透鏡體切割所需要之時間内調 整該f-θ物鏡50的焦點。例如，可容易地在約1〇毫秒至4〇毫 秒間之日守間内執行具有約100微米.的束焦點2偏移之完全線 掃描’及在某些情況下甚至少於5毫秒。因此，本發明在雷 射束的束路徑中使用可調適、可變形的鏡子達成諸如在飛 秒透鏡體摘出之實際可行的應用中所需要之聚焦偏移頻 率。 在根據第3及4圖的變型中’相同或具有相同效應之構 件k供與在第2圖中相同的參考數字，但是加入小寫體字 母。為了避免不需要的重複，參照先前關於第2圖之解釋， 除非在下列有其它方面指示出。 第3圖的典型具體實例亦在從雷射來源28a射出的雷射 束之束路徑中包含可調適的鏡子34a。但是，可調適的鏡子 34a位於光束傳播方向中之望遠鏡32a與掃瞄器44a間。因 此’攸望运鏡32a射出之經擴展的雷射束部分42a在望遠鏡 32a的入口邊上具有如雷射束30a般的基本平面波前。根據 欲設定的束焦點z位置’由鏡子34a反射及進入掃猫器44a的 雷射束（由62a表示)僅有部分具有彎曲的波前，其曲率程度 依束聚焦之想要的z位置而定。 為了完整性’在第3圖中指示出進一步的被動偏轉鏡子 64a，66a，然而它們在雷射束之發散上不具有效應。 根據第4圖’該雷射裝置的變型可沒有用於雷射束的束 13 201118418 擴展之望遠鏡而作用。反而，該可調適的鏡子鳥其自身為 束擴展光學儀ϋ的部分，其由可調適的鏡子施及進—步鏡 子68b組成之鏡子組合形成。在雷射束通的光束傳播方向 中k遇到此鏡子组合之第„鏡子為凸面鏡，同時第二遭遇 到的鏡子為凹面鏡。在所顯示出的典型實例巾，可變形的 鏡子34b構m面鏡，同時鏡子娜構成該凹面鏡及安裝 士為鏡面不可調適的靜止鏡子。要瞭解在經修改的具體實 例中，在該鏡子組合中第二遭遇到的凹面鏡可安裝成調適 地，同時該第一遭遇到的鏡子靜止。 該鏡子組合3扑烏以可與望遠鏡相比較的方式造成 束擴展。藉由合適地驅動可調適的鏡子34b之面，可以類似 於在第2及3圖的典型具體實例中之方式引起雷射束發散改 變，而在z方向中造成焦點位置52b之相應位移。 第4圖的典型具體實例由於其特別簡單的束引導優 良。再者，可能發生的成像誤差（視覺迷亂及散光)可由可變 形的鏡子34b補償，甚至在中立位置中。名稱‘‘中立位置，，想 要指為焦點位置52b假設一經定義的2參考位置之參考狀 態。對束擴展使用反射光學取代透射光學優良，特別是使 用比用於透鏡體切割的400奈米短之波長。 在上述描述的典型具體實例中，該可調適的鏡子34, 34a，34b為DMD型式(DMD :數位微鏡裝置）或LC〇s型式 (LCOS :液晶光學系統）或壓電控制的鏡子較佳。但是，明 顯不想要排除可用於該可變形的鏡子之其它作用及引動原 201118418 i:圖式簡單說明3 第1圖圖式地顯示出人類眼睛的一部分包含角膜之截 面圖，於其中指示出角膜透鏡體切割； 第2圖圖式地顯示出將根據本發明之裝置用於眼用雷 射外科的實施例； 第3圖顯示出此眼用雷射外科裝置的第一種變化；及 第4圖顯示出另一種變化。 【主要元件符號說明】 10...角膜 34...可變形的鏡子 12...光學軸 34a...可調適的鏡子 14...前表面 34b...可調適的鏡子 16...背表面 36...引動器配置 18...鞏膜及緣 38...控制單元 20...緣的邊緣 40...被動偏轉鏡子 22...基質内透鏡體 42...雷射束 24...平坦後端切割 42a...雷射束 26...彎曲前端切割 44.··掃瞄器 28...飛秒雷射來源 44a…掃猫 28a...雷射來源 46…偏轉鏡子 30·.·雷射束 48...偏轉鏡子 30a...雷射束 50...聚焦物鏡 30b...雷射束 ' 52...焦點位置 32...擴展光學儀器 52b...焦點位置 32a.··望遠鏡 54...鏡片 15 201118418 56...鏡片 66a...被動偏轉鏡子 58...入口鏡片 68b...鏡子 60...出口鏡片 a...透鏡體直徑 62a···雷射束 b...透鏡體厚度 64a...被動偏轉鏡子 d...角膜厚度 16201118418 VI. Description of the invention: t test affiliation L extension T T-collection ^ 3 The present invention relates to an optical imaging system that can be used particularly in ophthalmic laser surgical slings and can also be used for other In laser systems for processing tasks (eg, photovoltaic voltmeters or industrial material processing). I: Prior Art 3 In particular, the present invention provides an optical imaging system that allows the focus of a laser beam transmitted through the imaging system to be rapidly displaced in the z-direction; according to conventional nomenclature, the Z-direction represents the direction of the beam path (beam propagation direction). Then, the X or y direction is understood to be in any direction in a plane orthogonal to the z direction. In this plane, in order to scan the area of material to be processed by the laser beam, it is conventional to perform the movement of the laser beam by means of a scanner; the material to be processed may be a living or dead material. A laser system that emits short pulsed radiation in the femtosecond range is used in eye surgery, especially in the cornea (and also in human crystals) to produce intra-tissal incisions. The effect used in this example is a major discovery of optics which leads to the so-called photoblasting of the exposed tissue (ph〇t〇diSrUpti〇n). This generation of light blasting requires a relatively strong laser beam focusing by having a correspondingly large aperture for the focusing instrument n used for focusing. In the known ophthalmology fs laser system towel, the focusing optical instrument usually forms a planar field image by the so-called f-θ objective lens, and can avoid the undesired in 2 directions when the neon sweep (four) laser beam is formed. Beam focus shift. The fs laser system has an important position in ophthalmology (for example, for lasik applications). LASIK stands for laser in situ refractive corneal remodeling (1_ than 201118418 situ keratomileusis) and refers to the corneal treatment technique used to correct visual defects, which cuts a so-called part of the corneal tissue that is still partially connected to the corneal tissue. The "valve" then folds the flap to the side and, after folding the flap, removes the exposure by short-wave laser light (eg, an excimer laser emitted at 193 nm) according to the patient's specific resection profile. Matrix tissue. In order to create a S-cut, it is known to flatten the eye to be treated by pressing a flat plate and to guide the focus of the beam two-dimensionally on the plane inside the cornea. Since planar field imaging is provided by the f-theta objective, it does not require any 2 displacement of the focus. If it is desired to perform edge cutting of the flap from the substrate, it may be necessary to shift the focus position in the Z direction only in the edge region of the flap. Various solutions have been proposed for focus shifting in 2 directions in the prior art. WO 03/032803 A2 proposes an overall displacement of the focusing objective in the z-axis direction (i.e. along the beam path). A variant of this is to assemble the focusing objective into a zoom objective. However, both methods have the disadvantage of having to perform the mechanical displacement or zoom setting of the focusing objective very accurately, since it will be converted to focus position adjustment by 丨:i. For the desire to shift the focal point by a few microns between successive pulses of the laser beam, therefore, the zoom lens that requires the focusing objective or objective lens will be correspondingly rapidly mechanically displaced at the same distance. Conventional mechanical transmission equipment is not suitable for this. Another solution is presented in DE 10 2005 013 949 A1. The laser system therein has a two-lens extended optical instrument (a beam expander designed to be a telescope), a downstream scanner, and a focusing mirror behind the scanner. The entrance lens of the extended optical instrument (assembled as a concave lens) can be displaced in the beam direction (i.e., in the z-direction) by a linear actuator. The 201118418 displacement of this entrance lens modifies the divergence of the laser beam emitted from the extended optics. If the position of the focus mirror (f-θ objective lens) is still fixed, the focus position moves in the Z direction. The advantage of this Z-displacement solution for focusing optics is better reproducibility and higher displacement accuracy because the optical imaging system converts the displacement of the entrance lens of the beam expander into a displacement of the focus position ( It is reduced by, for example, a factor of 10). However, the rate at which the entrance lens can be achieved is limited by the beam focus displacement rate converted to the focal plane. For three-dimensional cutting (as required, for example, for the removal of corneal lens bodies), it is generally accepted that the focus adjustment method according to DE 10 2005 0139 49 A1 is faster than the method presented in WO 03/032803 A2, simply because of the adjustment In the example of the entrance lens of the beam expander, the subject to be moved is much less than in the example of adjusting the overall focusing optics. At the same time, the 'focusing optical instrument can easily weigh several kilograms, but it still has to move without vibration. On the other hand, the entrance lens of the beam expander can have a relatively small aperture and correspondingly small and lightweight. However, conventional linear actuators are not sufficient when it is desired to produce an intracorneal lens cut or another three-dimensional cut in an acceptably short time with a laser that repeats quickly enough. Conventional linear actuators can be used to guide the entrance lens of the beam expander with a tilt rate of, for example, between about 1 and 3 mm/sec. However, it can be tolerated for up to about 5 mm/sec. The mechanical guidance of the entrance lens. However, for lens body cutting, when using a fs laser in the two- to three-digit kilohertz range or even a faster repeating fs laser with the same z-focus adjustment principle, it will require at least 10 mm/sec or higher. The entrance lens adjustment rate, which cannot be achieved with the linear drive system commercially available from 201118418, is at least not a system that meets the need for adjustment accuracy and guidance accuracy. In addition to the linear displacement capability of the entrance lens of the beam expander, dechuan 2005 013 949 A1 proposes placing two concave mirrors in the beam path between the laser and the spotlight, the laser beam (hence its focus position) The divergence in the two directions can be varied by changing the mutual spacing of the concave mirrors. Again, the comparable limit exists in the mechanical adjustment speed. SUMMARY OF THE INVENTION One of the objects of the present invention is to provide an optical imaging system that is more suitable for three-dimensional focus guidance in material processing and particularly in ophthalmology. In order to achieve this object, the present invention provides an optical imaging system having at least one deformable mirror and an adjustment and control arrangement, wherein the configuration is coupled to the mirror and adapted by deformation of the mirror, particularly according to a predetermined focus displacement curve. To shift the image side focus of the imaging system in the direction of beam propagation. The deformable mirror and its use in laser systems are known per se. For example, 'in this regard, refer to S. Mian, P. Bierden' in Laser + Photonic 4/2007, pages 18-22, "Spieglein ' Spieglein. .., Technologische Fortschitte und Anwendungen verformbarer Mikrospiegel" [mirror, mirror..., technical development and application of deformable micromirrors]. In particular, according to the information in this paper, the deformable mirror can be divided into five different basic variants, in other words, a deformable MEMS mirror (MEMS: MEMS), a piezoelectric deformable mirror, Deformable film mirror, two-state deformable 6 201118418 mirror and ferromagnetic deformable mirror. The present invention is not intended to be limited to these non-(10) subtypes. In principle, any deformable mirror with the desired modification of the wavefront of the incident laser beam can be used in a pure system telescope. A faster beam focus shift can be achieved by beam steering with a fairy beam + using a deformable (adapted) mirror (compared to a conventional mechanical linear adjustment system, such as m-level sized mirrors) A known field of application is, for example, in astronomical observations, where the 'disturbed wavefront is converted into a plane wavefront by an adaptable mirror' in order to improve the image quality of the light received by the atmospheric disturbance. In contrast, the present invention does not attempt to eliminate undesired wavefronts by corresponding deformation of the deformable mirror. Instead, the present invention aims to morph the person on the mirror by means of a properly biliary mirror. The wavefront of the beam so that the image side focus of the imaging system (and therefore the beam focus) is displaced in the desired direction in the x direction. Preferably, the adjustment and control configuration is adapted to adjust the mirror to The substantially planar incident wave is converted into a reflected wave shape having a substantially uniform curved wavefront whose intensity of the wavefront curvature depends on the desired focal position in the direction of beam propagation. In terms of quality, the consistency of the wavefront curvature is desired. Therefore, the present invention substantially reverses the conventional use of a δ-perimeter mirror to improve the planarity of the wavefront, and deliberately produces an explicit from about a plane wave. The continuously variable wavefront curvature. The resulting wavefront curvature may mean an increase or decrease in divergence such that the beam focus is displaced in one direction or other from a predetermined neutral position. In a specific example, the mirror 7 201118418 can be placed in front of the telescope in the direction of beam propagation. On the other hand, in another embodiment, it may be arranged behind the telescope in the direction of beam propagation, but preferably before the focusing optics having at least a single lens, and before the scanner. Furthermore, according to still another specific example, it is understood that the beam expanding optical instrument is constructed from two mirrors and one of the mirrors is mounted as an adaptable deformable mirror, whereby the desired divergence can be introduced into the beam. in. Promoted by the present invention, rapid focus shifting in the Z direction is particularly attractive for use in those ophthalmology applications (its fs laser accommodating operation with fast repetitive focusing and the need for fast three dimensional tangential guidance - short processing time) . Accordingly, another aspect of the present invention provides an apparatus for ophthalmic f (four) families having a pulsed femtosecond f-beam source, a beam expanding optical instrument that extends the laser beam, and used downstream of the extended optical instrument a broom that deflects the laser beam in a plane perpendicular to the beam path, and a focusing optical instrument for focusing the laser beam downstream of the sweep (four), wherein the device has a mirror of The beam is transmitted in the middle, between the laser (four) and the focusing optics) and the adjustment and control of the program control is based on the intended to be generated in the patient's eye and by the control program: the cutting shape is adapted to deform The mirror is in the beam path and the displacement is broken.) The adjustment and control configuration can be adapted to control the beam focus of the beam to be displaced in the beam path direction by at least heart = 150 micrometers, preferably at least 2 micrometers, preferably from the fast three-dimensional shape of the invention, should be 201118418 It is used as a corneal lens body, in which a lenticular volume unit is cut out from the mode film f to correct the corner 臈 refraction. For this reason, the focus of accurate and fast three-dimensional positioning of the fs laser pulse is important. There is no problem with the corresponding fast operation of this scanner in the x y direction. For example, conventional mirror scanners that operate according to the galvanometer principle can easily ensure the required deflection even when the pulses are repeated in the megahertz range. The beam focus can be easily shifted in the high range (two digits to three digit micrometers) in the Z direction, within a few milliseconds or at least tens of milliseconds, by using a deformable mirror. For corneal lens extraction, for example, it allows for a full lens cut in a few minutes (eg, 2_4 minutes) or even less than i minutes (depending on the size of the lens body), which will be operated by the patient here. The uncomfortableness suffered underneath is limited to the shortest possible time. Furthermore, the present invention opens the opportunity to use a quasi-molecular laser to refractively correct the eye as previously known, since the high accuracy and reproducibility of the z-position of the beam focus during lens extraction allows beam guidance and correction The visual defects match exactly. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail below with the aid of additional figures, in which: Figure 1 is a schematic representation of a corneal-like mask of a human eye in which a corneal lens is indicated Cutting; FIG. 2 is a view showing an embodiment in which the device according to the present invention is applied to ophthalmic laser surgery; FIG. 3 shows a first variation of the ophthalmic laser surgical device; and FIG. 4 shows Another change. 201118418 [Embodiment 3] First, refer to Fig. 1. It shows the cornea of the human eye (indicated by 10) in cross section. The optical axis of the eye (viewing axis) is indicated by dots and dashes and is indicated by 12. The cornea 10 has a front surface 14 and a back surface 16. The thickness d of the human eye typically ranges from about 500 microns and can of course vary upwards or downwards depending on the individual. The sclera and margin of the eye are indicated by 18 in Figure 1 and the edge of the margin is indicated by 20. In Fig. 1, the intraocular lens to be cut by the focused fs laser radiation treatment or more precisely the intra-matrix lens body 22 is also indicated by a dash, which is then operatively removed via the opening in the cornea 10 to be introduced laterally. This opening can also be produced by laser cutting. The femtosecond lens extraction allows correction of visual defects (e.g., myopia and myopic astigmatism). The lens body 22 is conventionally produced by a substantially flat rear end cut 24 and a curved front end cut 26. The lens body diameter (represented by a in Fig. 1) ranges, for example, between about 6 and 8 mm, while a typical lens thickness (indicated by b) is, for example, about 80-100 microns. With the thickness values of these lenses, visual defects of about -5 dpt to -6 dpt can be corrected. It is to be understood that both the lens body diameter and the lens body thickness may vary depending on the intensity of the visual defect to be corrected. However, in any event, the lens body thickness will often be tens of microns, which is associated with approximately the lower edge of the flat lens body (defined by the rear lens body cut 24), meaning that the laser beam is at the top of the lens body. In the line scan on the lens body 22 (where the lens body 22 has the largest thickness), the beam focus of the laser beam must perform an offset corresponding to the thickness of the lens body in the beam propagation direction. Now, also refer to Figure 2. The laser device shown therein comprises a femtosecond laser source 28 which is for example formed by a fiber laser which produces a pulse 10 201118418 period in the femtosecond range and a pulse repetition rate at a high (two to three digits) Pulsed laser radiation 30 in the kilohertz range (or even better in the range of millions of Hertz). The resulting laser beam is expanded by an expanding optical instrument 32. In the direction of beam propagation, there is an effective deformable mirror 34 in front of the expanding optics 32, the deformed state of which can be adjusted by an actuator configuration, generally indicated at 36, which is in turn driven by a programmed control unit 38. The mirror 34 has a plurality of individual mirror faces that can be adjusted by the actuator arrangement 36, and the actuator arrangement 36 can have, for example, a piezoelectric drive element, a MEMS drive element, a drive element (DMD: digital micromirror device) or LCD drive element (LCD: liquid crystal device). Again, in the typical example shown, the front of the mirror material is the passive deflection mirror 40, but it has no or at least no substantial effect on the wavefront characteristics (and thus the divergence of the laser beam 3〇). . Expanded by the extended optics rhyme (4) beam (and by the 42 table (five) followed by the trip to the sweeping cat secret, the purpose of which is to transmit the beam to the (four) direction; the coordinate system indicated in Fig. 2 is also positive) The beam 42' in the intersecting xy plane therefore scans the laser beam over the area of the eye to be treated. In the typical example shown, the sweeper acts according to the galvanometer principle and by means of two tiltable deflection mirrors 46, 48 (which can be constructed from the control unit side. It is understood that scanning can also be performed according to other principles. The scanner (eg, by a suitably controllable crystal scan). The sweeper 44 then focuses the objective 50 (especially fe is focused onto the focus position 52). The typical solid lion is shown with two lenses 54 mounted. 56. To understand that the objective lens is easily equipped with any other desired number of lenses for 201118418. A specific example of a focusing objective (such as an f-theta objective) results in planar field imaging where the focal position 50 is always orthogonal to the z-direction. The plane is independent of the deflection angle of the laser beam. In the typical example shown, the beam expanding optical instrument 32 is comprised of an entrance lens 58 having a negative refractive power (concave lens) and an exit having a positive refractive power (converging lens). The Galilean telescope of lens 60 is formed. Furthermore, the Keppler version of the telescope with two convex lenses is possible. According to a typical example, the incident lens is incident on the mirror. The laser beam 3〇 on the sub-34 has a substantially planar wavefront which, from a predetermined reference position (neutral position) of the focus position 52, is reflected from the mirror 34 with substantially no bending effect, thus substantially preserving its plane wave Front. For the focus position 52 to be displaced from the neutral position in the z-direction, the control unit 38 can adjust the mirror 34 via the intermediate actuator configuration 36 so that the plane wavefront of the incident laser beam 3〇 is converted into a substantially uniform bend. Wavefront. Depending on the nature of the wavefront curvature, this can cause the laser beam to diverge or converge. This change in beam divergence causes the focus position 52 to shift in the z direction, while other aspects extend the optical instrument^ fixedly configured The focus objective 50 is also not moved. The control unit 38 controls the actuator arrangement 36 according to the cutting curve to be produced in the eye, thus the deformation state of the mirror 34. The corresponding control program for the control unit 38 is stored in the memory (no detail The ground curve is shown in detail. The cutting curve or control program specifies that the focus of the optical imaging system is shifted in two directions at different positions in the x · y plane. The method, and in the concept of the present invention, is a typical focus shift curve that can drive and illuminate the accuracy and speed of the actuator suitable for the 12 201118418 mirror 34 so that it can be achieved in tens of milliseconds or even milliseconds. The beam focus is offset by z in the range of tens of micrometers. Therefore, the focus of the f-theta objective 50 can be adjusted in the time required for the fs laser system to effectively and quickly lance the lens. For example, it can be easily A full line scan with a beam focus 2 offset of about 100 microns. and in some cases even less than 5 milliseconds is performed in a day between 1 millisecond and 4 milliseconds. Therefore, the present invention is in a laser beam The use of an adaptable, deformable mirror in the beam path achieves the focus offset frequency required in practical applications such as femtosecond lens extraction. In the modification according to Figs. 3 and 4, the member k which is the same or has the same effect is given the same reference numeral as in Fig. 2, but the lowercase letter is added. In order to avoid unnecessary duplication, reference is made to the previous explanation of Fig. 2, unless otherwise indicated below. A typical embodiment of Fig. 3 also includes an adaptable mirror 34a in the beam path of the laser beam emerging from the laser source 28a. However, the adaptable mirror 34a is located between the telescope 32a and the scanner 44a in the direction of beam propagation. Therefore, the expanded laser beam portion 42a emitted from the viewing mirror 32a has a substantially planar wavefront such as the laser beam 30a on the entrance side of the telescope 32a. According to the beam focus z position to be set, the laser beam reflected by the mirror 34a and entering the scanner 44a (represented by 62a) has only a portion having a curved wavefront whose degree of curvature depends on the desired z position of the beam focus. set. For the sake of completeness, further passive deflection mirrors 64a, 66a are indicated in Figure 3, however they have no effect on the divergence of the laser beam. According to Fig. 4, the variant of the laser device can be used without the telescope for the beam of the laser beam 13 201118418. Instead, the tunable mirror bird itself is part of the beam-expanding optics, which is formed by a combination of mirrors that are adapted to the mirror 68b. In the direction of beam propagation of the laser beam, the mirror „the mirror is a convex mirror, and the second encountered mirror is a concave mirror. In the typical example shown, the deformable mirror 34b is m-faced. Mirror, while mirror Na constitutes the concave mirror and the mount is a mirror that is not adaptable to the static mirror. It is understood that in the modified specific example, the second encountered concave mirror in the mirror assembly can be installed to be adaptive, and the first The encountered mirror is still. The mirror combination 3 causes the beam to expand in a manner comparable to that of the telescope. By suitably driving the face of the adjustable mirror 34b, it can be similar to the typical example in Figures 2 and 3. The mode in which the laser beam divergence changes is caused, and the corresponding displacement of the focus position 52b is caused in the z direction. The typical example of Fig. 4 is excellent because of its particularly simple beam guidance. Furthermore, imaging errors that may occur (visual fans) Chaos and astigmatism can be compensated by the deformable mirror 34b, even in the neutral position. The name ''neutral position,') is intended to be the focus position 52b assumed to be fixed Reference state of the reference position of the sense 2. It is excellent for beam extension to use reflective optics instead of transmission optics, especially using a wavelength shorter than 400 nm for lens body cutting. In the typical embodiment described above, the adaptable The mirrors 34, 34a, 34b are preferably DMD type (DMD: digital micromirror device) or LC〇s type (LCOS: liquid crystal optical system) or piezoelectrically controlled mirror. However, it is obviously not intended to exclude the use of the deformable Other functions of the mirror and the original 201118418 i: Simple description of the figure 3 Figure 1 shows a part of the human eye including a sectional view of the cornea, which indicates the corneal lens cutting; Figure 2 shows An embodiment of the device according to the invention for ophthalmic laser surgery; Figure 3 shows a first variation of the ophthalmic laser surgical device; and Figure 4 shows another variation. 10... cornea 34... deformable mirror 12... optical axis 34a... adjustable mirror 14... front surface 34b... adjustable mirror 16... back surface 36. .. actuator configuration 18 ... sclera and edge 38. The control unit 20...the edge 40 of the edge...the passive deflection mirror 22...the inner lens body 42...the laser beam 24...the flat rear end cutting 42a...the laser beam 26. .. curved front end cutting 44.. scanner 28... femtosecond laser source 44a... sweeping cat 28a... laser source 46... deflection mirror 30·. laser beam 48... deflection mirror 30a ...beam beam 50...focusing objective lens 30b...laser beam '52...focus position 32...expansion optical instrument 52b...focus position 32a.·.telescope 54...lens 15 201118418 56...lens 66a...passive deflection mirror 58...inlet lens 68b...mirror 60...outlet lens a...lens body diameter 62a···laser beam b...lens body Thickness 64a... passive deflection mirror d... corneal thickness 16