I29Q613 九、發明說明: 【發明所屬之技術領域】 本發明係有關於一種用以對液晶面板用之玻璃基板等 基板,測定基板上測定對象處之位置的方法及裝置,以及 使用其之位置測定系統。 【先前技術】 爲了檢查基板之製作尺寸精度,已經有人這樣做:於 基台或移動載台上載置基板等測定對象物,以可以相對於 φ 測定對象物移動的攝影機來拍攝測定對象物,處理拍攝所 得之圖像,藉以求取測定對象處之位置。例如:專利文獻 1中有如下記載:於固定載物台上載置測定對象物,以朝1 個方向移動之載物台所搭載的攝影機來拍攝測定對象物。 [專利文獻1]日本特開2003-286 1 1 【發明內容】 [發明之揭示] [發明所欲解決之課題] • 基台上載台之移動量,精密地測定或控制係比較容 易;但用來將載台上之測定對象物從上方拍攝的攝影機之 視野位置,則會隨著攝影機之移動而產生較大的誤差。此 視野位置之誤差,一方面起因於攝影機移動量本身的誤 差,另一方面起因於攝影機姿態之變化。攝影機姿態之變 化所造成視野位置之誤差,是由於隨著攝影機姿態之變 化,攝影機之光軸方向發生變化,結果,測定對象物上之 視野之位置發生變化而發生。 I29Q613 藉由機械上的精度係很難充分減少攝影機視野位置之 誤差。尤其,攝影機之姿態發生變化所造成的誤差,即便 對於一點點的攝影機之傾斜,也會敏感,所以,充分減少 誤差是非常困難的。例如:假設攝影機與測定對象物間的 距離爲200mm,則攝影機之斜度只要1/ 1〇〇〇度,測定對 象物上之視野之位置之變動大小就有3 · 5 // m。每次移動攝 影機,就難以避免攝影機姿態這個程度的變動發生,在像 檢查液晶面板之玻璃基板時那樣般要求高精度測定時的情 況,本來就不能容許此誤差。 本發明之目的爲:在測定基板上測定對象處之位置 時,使攝影機之移動量誤差及攝影機之姿態變動所造成之 攝影機之視野位置之誤差,不會影響位置測定結果。 [用以解決課題之手段] (1)本發明之位置測定方法:準備位置測定裝置,該 位置測定裝置具有:基台;在前述基台上朝第1方向移動 的載台;用來測定前述載台移動量的移動量測定器;固定 • 於前述基台的架台;配備於前述架台,以與第1方向正交 之第2方向作爲可動方向的攝影機移動機構;被前述攝影 機移動機構支撐,在前述基台之上方朝第2方向移動的攝 影機;以及基準標尺,係沿著垂直於前述載台移動方向之 方向配備於載台上,在被前述攝影機拍攝後,用以在拍攝 所得之圖像中提供攝影機視野位置相關之資訊, 於前述載台上載置作爲測定對象的基板,以前述攝影 機拍攝前述基板上測定對象處及基準標尺中之任一者,不 I29Q613 移動前述攝影機移動機構,保持於前述拍攝後之原狀下, 僅使前述載台移動,且以前述攝影機拍攝前述基板上測定 對象處及基準標尺中之另一者,藉由前述移動量測定器來 測定載台在前述移動下之移動量,使用所得到測定對象處 之圖像及基準標尺之圖像以及載台之移動量來求取測定對 象處之位置。 「移動量測定器」,不限於如線性編碼器般用以直接 測定載台移動量的裝置,也可以是間接地測定載台移動量 Φ 的裝置,例如:從載台移動量之指令値取得移動量的裝置。 「架台」較佳爲:在基台上架設成跨越載台之移動區 域,使得配備於該架台之攝影機移動機構所支撐的攝影機 可以從上方拍攝載置於載台上的基板或基準標尺。 攝影機,因爲被以第2方向作爲可動方向的攝影機移 動機構所支撐,朝前述第2方向移動,故移動攝影機移動 機構,即可使攝影機朝第2方向移動,另一方面,不移動 攝影機移動機構時,攝影機不移動,保持原狀。 # 基準標尺因配備於載台上,故在拍攝此基準標尺後之 攝影機之圖像中所提供攝影機視野之位置資訊就成爲以載 台位置作爲基準的資訊。此基準標尺因係沿著垂直於前述 載台移動方向的方向,亦即,沿著作爲攝影機移動方向之 前述第2方向而被配備,故在攝影機移動方向之各移動位 置拍攝此基準標尺,即可獲得視野之位置資訊。此基準標 尺較佳爲用以提供前述第1方向及前述第2方向相關之視 野之位置資訊者。又,此基準標尺較佳爲具有用以提供前 I29Q613. 述第1方向及前述第2方向資訊之圖案者,於前述圖案也 可以附加用以提供該圖案前述兩方向之座標値的資訊。 本發明之位置測定方法中利用3種資訊。被利用之第 1資訊是基準標尺之圖像。藉由此圖像可以求取拍攝基準 標尺時攝影機視野之位置。此視野之位置是拍攝基準標尺 時基準標尺之位置,亦即,是以載台當時之位置作爲基準 的位置。視野之位置因爲攝影機移動量之誤差及攝影機姿 態之變動而產生誤差,但是即便存在有這樣的視野位置誤 II 差,利用從拍攝得到之基準標尺圖像求得的視野位置,視 野位置之誤差就不會影響位置測定結果。 被利用之第2資訊是拍攝基準標尺時與拍攝測定對象 處時之間之載台移動量。若使用第1資訊及第2資訊,即 可求取以拍攝基準標尺時載台之位置作爲基準的拍攝測定 對象處時視野之位置。 被利用之第3資訊是測定對象處之圖像。藉由此圖像 可以求取以拍攝測定對象處時攝影機之視野作爲基準的測 • 定對象處之位置。因此,若使用所有的資訊,即可求取以 拍攝基準標尺時載台之位置作爲基準的測定對象處之位 置。若在測定載台之移動量時判明載台與基台間之相對位 置關係,即可藉由本發明之位置測定方法來求取以基台作 爲基準的測定對象處之位置。 依據本發明之位置測定方法,在測定基板上測定對象 處之位置時,藉由基準標尺之拍攝,可以使攝影機之移動 量誤差及攝影機之姿態變動所造成之攝影機視野位置誤差 I29Q613 不影響位置測定結果。而且,以攝影機拍攝基板上之測定 對象處及基準標尺中任一者之後,到以攝影機拍攝基板上 之測定對象處及基準標尺中之另一者之前,不移動攝影 機,在此狀態,攝影機相對於基台係靜止著,故可以防止 在此期間攝影機視野位置產生誤差。因此,測定對象處之 位置之測定精度使提高。 (2)本發明之位置測定方法之一個實施型態爲:準備 前述位置測定裝置,於前述載台上載置作爲測定對象的基 φ 板,以前述攝影機拍攝前述基板上之測定對象處,不移動 前述攝影機移動機構,保持其前述拍攝後之原狀下,僅使 前述載台移動,且以前述攝影機拍攝基準標尺,藉由前述 移動量測定器來測定載台在前述移動下之移動量,使用所 得到測定對象處之圖像及基準標尺之圖像以及載台之移動 量來求取測定對象處之位置。 在本實施型態之位置測定方法中,是拍攝完測定對象 處之後再拍攝基準標尺。此時,也可以將此順序顛倒,拍 • 攝完基準標尺之後再拍攝測定對象處,不過,在此情況下, 或由於基板之載置姿態在面內旋轉而偏移,或由於拍攝對 象之形成位置之精度低等原因,有時和假定相反地在載台 移動後之視野內找不到測定對象處,此時,必須變更尋找 測定對象處的假定位置。同時,在移動了攝影機位置之情 況下,因恐怕此攝影機之移動導致誤差產生,故先拍攝基 準標尺的方法,必須再從基準標尺之拍攝起重做。 相對於此,拍攝完測定對象處之後再拍攝基準標尺的 1290613 這個實施型態之位置測定方法,係若在包含有測定對象處 假定位置的視野內找不到測定對象處,則每次一點點地移 動載台及攝影機中之任一者或兩者,搜尋測定對象處,且 自已拍攝到測定對象處的位置,在不移動攝影機之狀態 下,僅移動載台,再拍攝基準標尺即可,故不必重新拍攝 基準標尺。 (3)在上述(2)之實施型態中,也可以準備前述位置測 定裝置,於前述載台上載置作爲測定對象的基板,以前述 0 攝影機拍攝前述基板上之第1測定對象處,在不移動前述 攝影機移動機構之狀態下,使前述載台做第1移動,以前 述攝影機拍攝基準標尺,藉以獲得基準標尺之第1圖像, 藉由前述移動量測定器來測定載台在第1移動下之第丨移 動量,在不移動前述攝影機移動機構之狀態下,使前述載 台做第2移動,且以前述攝影機拍攝假定存在有第2測定 對象處的基板表面處, 若拍攝得到的圖像存在有第2測定對象處,則採用此 # 圖像來作爲第2測定對象處之圖像;若拍攝得到的圖像未 存在有第2測定對象處,則使載台或攝影機移動機構作細 微移動且進行拍攝,如此反覆,直到成功拍攝第2測定對 象處爲止, 藉由前述移動量測定器來測定前述載台之第2移動 量’或是如前所述使載台作細微移動後,藉由前述移動量 測定器來測定第2移動量加上微動部分所得的累積移動 量,來作爲第2移動量, -10- 1290613 在成功拍攝第2測定對象處之前 機構之情況下,從成功拍攝第2測定 T移動攝影機移動機構,在此狀態下 移動,且以前述攝影機拍攝基準標尺 之第2圖像,藉由前述移動量測定器 動量, 使用既得之第1及第2測定對象 之第1圖像、載台之第1及第2移動 0 準檩尺之第2圖像及載台之第3移動 測定對象處之位置。 依據本實施型態,可以用少的載 載台移動方向分開的測定對象處之位 (4)上述(2)之實施型態中,也可 裝置,該位置測定裝置具有··可以彼 影機移動機構及第2攝影機移動機構 移動機構支撐的第1攝影機及被第2 • 的第2攝影機;且第1及第2攝影機 載台移動方向的方向分開著,於前述 對象的基板,以第1攝影機拍攝前述 象處,且以第2攝影機拍攝第2測定 1及第2攝影機移動機構之狀態下, 第1及第2攝影機分別拍攝基準標尺 定器來測定載台在前述移動下之移動 及第2測定對象處之圖像、以第1及 ,移動了攝影機移動 對象處時之狀態起, ,使前述載台做第3 ,藉以獲得基準標尺 來測定載台之第3移 處之圖像、基準標尺 量,以及存在時,基 量,來求取第1及第2 台移動來測定2個在 置° 以準備前述位置測定 此獨立移動的第1攝 ;以及被桌1攝影機 攝影機移動機構支撐 之視野彼此在垂直於 載台上載置作爲測定 基板上之第1測定對 對象處,在不移動第 使前述載台移動,以 ,藉由前述移動量測 量,使用既得之第1 第2攝影機分別拍攝 -11- I29Q613. 得到基準標尺之第1及第2圖像以及載台之移動量,來求 取第1及第2測定對象處之位置。 第1及第2攝影機較佳爲:分別透過第1及第2攝影 機移動機構被沿著垂直於該載台移動方向的方向架設的架 台所支撐,且跨越載台之移動區域,使得可以確保在垂直 於載台移動方向之方向上分開的視野。 利用第1及第2攝影機來對第1及第2測定對象處之 拍攝’及利用第1及第2攝影機來對基準標尺之拍攝較佳 ϋ 爲:以第1及第2攝影機同時分別進行。 依據本實施型態,可以使用2台攝影機,以少的載台 移動來測定2個在垂直於載台移動方向之方向上分開的測 定對象處之位置。 (5)上述(2)之實施型態中,亦可準備前述位置測定裝 置,該位置測定裝置具有:可以彼此獨立移動的第1攝影 機移動機構及第2攝影機移動機構,以及被第1攝影機移 動機構支撐的第1攝影機及被第2攝影機移動機構支撐的 # 第2攝影機;且第1及第2攝影機之視野彼此在垂直於載 台移動方向的方向分開著,於前述載台上載置作爲測定對 象的基板,以第1攝影機拍攝前述基板上之第1測定對象 處,不移動第1攝影機移動機構,保持其前述拍攝後之原 狀下,使前述載台做第1移動,且以第2攝影機拍攝前述 基板上之第2測定對象處,藉由前述移動量測定器來測定 載台在第1移動下之第1移動量,在不移動第1及第2攝 影機移動機構之狀態下’使前述載台做第2移動,以第1 -12- 1290613· 及第2攝影機分別拍攝基準標尺,藉由前述移動量測定器 來測定載台在第2移動下之第2移動量,使用既得之第1 及第2測定對象處之圖像、以第1及第2攝影機分別拍攝 得到基準標尺之第1及第2圖像,以及載台之第1及第2 移動量,來求取第1及第2測定對象處之位置。 當移動第2攝影機移動機構可能改變第1攝影機之視 野位置時,較佳爲:在自第1測定對象處之拍攝至第2測 定對象處之拍攝之期間,不僅不移動第1攝影機移動機 φ 構,也不移動第2攝影機移動機構。因此,若爲了以第2 攝影機拍攝第2測定對象處,必須移動第2攝影機移動機 構,則較佳爲:在以第1攝影機拍攝第1測定對象處之前, 事先移動第2攝影機移動機構。 依據本實施型態,可以使用2台攝影機,以少的載台 移動來測定基板上任意位置之2個測定對象處之位置。 本實施型態中,也可以在第1測定對象處之拍攝(第1 拍攝)與第2測定對象處之拍攝(第2拍攝)之間,使用第1 • 攝影機、第2攝影機或其他攝影機,來拍攝其他之測定對 象處。在此情況下,使載台自第1拍攝至第2拍攝之累積 移動量(自進行第1拍攝後的載台位置至進行第2拍攝後的 載台位置的距離)爲載台之第1移動量。 本實施型態中,也可以使用讓個別的攝影機移動機構 去支撐第3攝影機、第4攝影機等更多的攝影機所構成的 位置測定裝置,邊移動載台,邊依序拍攝與攝影機個數相 對應的測定對象處,利用各攝影機來對基準標尺之拍攝則 -13- 1290613 在共通之載台位置來進行。在此情況下,若測定對象處中 有2個以上在載台之移動方向分開著,則此等測定對象處 可以用共通之攝影機來拍攝,因此,可以測定比攝影機個 數更多個數的測定對象處之位置。 又,若測定對象處中有2個以上在垂直於載台移動方 向之方向上分開著,則此等測定對象處可以在共通之載台 位置拍攝。很顯然地,若移動攝影機移動機構,則不論攝 影機之個數爲何,可以測定的測定對象處之個數都沒有限 制。但是,在移動完攝影機移動機構之後接著要再移動此 攝影機移動機構的這段期間,分別都要以被此攝影機移動 機構支撐的攝影機來拍攝基準標尺一次。 (6) 上述(1)〜(5)中任一項之位置測定方法中,也可以 於前述基板上設有可以拍攝的圖案,前述基板上之測定對 象處是自前述圖案選出的至少2處基準標記,使用既求得 之至少2處之基準標記之位置,進一步求取前述圖案之位 置及姿態。 (7) 上述(1)〜(5)中任一項之位置測定方法中,也可以 於前述基板上設有可以拍攝的圖案,前述基板上之測定對 象處是自前述圖案選出的第1點及第2點,使用既求得第 1點及第2點之位置,來進一步求取第1點與第2點之間的 距離。 (8) 上述(1)〜(5)中任一項之位置測定方法中,也可以 於前述基板上設有可以拍攝的圖案,前述基板上之測定對 象處是自前述圖案選出的第1、第2、第3及第4點,使用 -14- 1290613 既求得第1、第2、第3及第4點之位置,來進一 接第1點與第2點的直線與連接第3點與第4點 成的角度。 第2點及第3點也可以爲共通的1個點。 依據本實施型態,可以獲得圖案變形相關的 其在假定2條直線爲正交之下選擇測定對象之 下,會測定正交度,故可以獲得靈敏的變形資訊 (9)本發明之位置測定裝置,具有:基台; φ 前述基台上朝第1方向移動;移動量測定器,用 述載台移動量;架台,固定於前述基台;攝影機穆 配備於前述架台,以與第1方向正交的第2方向 方向;攝影機,被前述攝影機移動機構支撐,在 之上方朝第2方向移動;以及基準標尺,沿著垂 載台移動方向的方向配備於載台上,在被前述攝 後’用以在拍攝所得之圖像中提供攝影機視野位 資訊。 # 依據本發明之位置測定裝置,藉由基準標尺 可以使攝影機之移動量誤差及攝影機之姿態變動 攝影機視野位置之誤差不影響位置測定結果。 而且,因爲在拍攝基板上之測定對象處及基 期間,攝影機相對於基台係靜止著,故可以防止 產生攝影機視野位置之誤差。因此,測定對象處 定精度便提高。 (1 0)本發明之位置測定裝置之一個實施型態 步求取連 的直線所 資訊。尤 點之情況 〇 載台,在 來測定前 p動機構, 作爲可動 前述基台 直於前述 影機拍攝 置相關之 之拍攝, 所造成之 準標尺之 在此期間 位置之測 中,前述 -15- 1290613. 基準標尺,係隔著前述載台上待載置基板之區域配備於載 台移動方向之兩側。 依據本實施型態,若已知兩側基準標尺彼此之位置關 係,則也可以利用任一個基準標尺,故藉由適當選擇要利 用之基準標尺,即可減少載台之移動量。 (11)本發明之位置測定系統,係具備上述(9)或(10)之 位置測定裝置,以及連接於前述位置測定裝置後能互相傳 輸資訊的控制裝置,前述控制裝置具備用來執行控制程式 Φ 的電腦,前述控制程式具備以下的步驟:以前述攝影機拍 攝載置於前述位置測定裝置之載台的基板上測定對象處及 基準標尺中之任一者,不移動前述攝影機移動機構,保持 其前述拍攝後之原狀下,僅使前述載台移動,以前述攝影 機拍攝前述基板上測定對象處及基準標尺中之另一者,藉 由前述移動量測定器來測定載台在前述移動下之移動量, 使用既得測定對象處之圖像及基準標尺之圖像以及載台之 移動量,來求取測定對象處之位置。 • 依據本發明之位置測定系統,在測定基板上測定對象 處之位置時,藉由基準標尺之拍攝,可以使攝影機之移動 量誤差及攝影機之姿態變動所造成之攝影機視野位置之誤 差不影響位置測定結果。而且’在拍攝基板上之測定對象 處及基準標尺之期間,攝影機相對於基台係靜止著,故可 以防止在此期間產生攝影機視野位置之誤差。因此,測定 對象處之位置之測定精度便提高。 [發明之功效] -16- I29Q613· 依據本發明,在測定基板上之測定對象處之位置時, 藉由基準標尺之拍攝,可以使攝影機之移動量誤差及攝影 機之姿態變動所造成之攝影機視野位置之誤差不影響位置 測定結果,而且,在拍攝基板上之測定對象處及基準標尺 之期間,攝影機相對於基台係靜止著,故可以防止在此期 間產生攝影機視野位置之誤差。因此,測定對象處之位置 之測定精度便提高。 【實施方式】 # [用以實施發明之最佳型態] 以下,有關本發明之實施型態,將根據圖式詳細說明。 第1圖顯示有關本發明一個實施型態之位置測定系統 之槪略構成的立體圖;第2圖爲位置測定裝置之俯視圖。 本實施型態之位置測定系統如第1圖所示具備位置測 定裝置1,以及以可以互相傳輸資訊之方式連接於此位置 測定裝置1的控制裝置2。又,控制裝置2內部具有用以執 行控制程式的電腦,該控制程式用以控制位置測定裝置1。 # 位置測定裝置1具備有:花崗石等石製之基台3;可 以沿著設置於其上之一對導軌4移動的載台5 ;以跨越此 載台5之方式架設於基台3上固定位置的門型架台6;複數 個設於此架台6內的未圖示攝影機移動機構;以及複數台 (本實施型態中爲3台)被各攝影機移動機構支撐的攝影機 A〜C 0 矩形板狀載台5可以藉由未圖示之線性馬達等驅動機 構而朝作爲第1方向的圖之y方向(第2圖之左右方向)移 -17- I29Q613. 動。各攝影機A〜C可以藉由以身爲正交於第1方向之第2 方向的圖之X方向(第2圖之上下方向)作爲可動方向的各 攝影機移動機構,而在X方向彼此獨立移動。 於基台3上設有沿著身爲載台5移動方向之y方向延 伸的線性標尺10 ;於載台5之下面設有與該載台5成爲一 體地移動的未圖示之編碼器讀取頭。藉由線性標尺1 〇及編 碼器讀取頭來構成線性編碼器,其係當作測定載台5之y 方向移動量的移動量測定器。 φ 線性標尺1 〇及編碼器讀取頭,係各設置2個,如此構 成2個線性編碼器’各線性編碼器分別用以測定載台$之 第1圖上眼前側及對面側之移動量。 各編碼器讀取頭配備有投光部及受光部,在受光部接 收自投光部射出且在線性標尺1 〇調變後的反射光,即可獲 得與載台5移動量對應數目的脈衝訊號。此外,於各線性 標尺1 0之1處設有原點圖案,如此也可以獲得載台位置之 原點訊號。線性標尺1 0設置有2個的理由是:補正因載台 Φ 5姿態之偏搖(水平面內回転)所造成載台移動量之誤差。 可以使用雷射干涉計或其他公知的移動量測定器來代 替線性編碼器。 於基台3上設有與載台5側面相對向之雷射位移計 1 1,藉由此雷射位移計1 1,以載台5之側面作爲對象物來 進行位移測定。 此雷射位移計1 1,係具備用以朝對象物照射雷射光束 的投光光學系’以及透過受光透鏡在位置檢測元件接收來 -18- 1290613 自對象物之反射光的受光光學系,投光光軸與受光光軸係 在對象物附近以既定之交叉角相交,利用對象物上之雷射 光束之點(spot)在位置檢測元件上成像所產生之光束點像 (beam spot)之位置在至對象物之距離改變後會改變,且利 用三角測距之原理,以求取至對象物之距離或距離之變化 量。利用此雷射位移計1 1所得之位移測定結果,係作爲代 表載台5之移動所引起的載台5在X方向之位移量的値, 利用來補正作爲載置於載台5上之測定對象的基板1 2上之 • 測定對象處相關之位置測定結果。第1圖、2圖係圖示雷 射位移計1 1,以下之圖式則省略雷射位移計1 1之圖示。 供身爲測定對象的基板1 2載置的載台5,係與基台3 同樣地爲花崗岩等之石製,於此載台5設有用來以抵接之 方式將基板1 2定位的定位銷、自基板1 2下吸空気藉以使 基板1 2緊貼於載台5的吸附孔。 此外,於載台5上靠一端(圖之左端)之處,設有在與 載台5移動方向(y方向)垂直之X方向延伸的基準標尺13, • 此基準標尺Π用以在拍攝圖像中提供在被各攝影機A〜C 拍攝後各攝影機A〜C之視野位置相關的資訊。 基板12例如爲液晶面板用玻璃基板,在X方向有 7 3 0mm ’在y方向有920mm之大小。於基板12上藉由金屬 膜之蝕刻形成有基準標記及未圖示之配線圖案。第2圖之 十字標記P、Q、R、S是基準標記。必須在此基板1 2之全 域以±0.5 // m之精度進行位置測定。 架台6內部具有的各攝影機移動機構,係用以使各攝 -19- 1290613 影機A〜C朝χ方向移動,以拍攝載置於載台5上之基板 1 2者。此攝影機移動機構,係具有線性編碼器,邊以此線 性編碼器測定各攝影機A〜C在χ方向上之移動量,邊使各 攝影機A〜C移動至控制裝置2所指示的χ座標。因攝影機 移動量之誤差,係被基準標尺1 3之拍攝所補正,故此線性 編碼器也可以使用分解能低的,如1 V m的粗糙的線性編碼 器。 各攝影機A〜C構造上如顯微鏡般具有物鏡,且具備2 > 次元CCD拍攝元件。可以藉由物鏡之更換來變更拍攝倍 率。調至最高倍率時基板1 2上視野之大小,係在第2圖之 χ方向上爲144/zm,在y方向上爲110//m。 控制裝置2具備鍵盤及顯示器,可以對位置測定裝置 1即時傳送指令,或觀察以位置測定裝置1拍攝所得之圖 像,或輸入用以控制位置測定裝置1的程式。用以控制位 置測定裝置1之程式也可以經由網路自外部下載。 第3圖爲顯示第2圖中基準標尺13 —部分的放大圖, | 第2圖之χ方向(上下方向)對應於第3圖之上下方向,第2 圖之y方向(左右方向)對應於第3圖之左右方向。 此基準標尺1 3係由鈉玻璃等玻璃製成,本實施型態 中,在χ方向(上下方向)形成有週期爲l〇〇//m之重複圖 案。此重複圖案,係十字圖案配置於橫長的矩形圖案內之 中央,且與矩形圖案上下之邊連接,不與左右之邊連接之 圖案。 此矩形圖案在其χ方向(上下方向)之長度爲l〇〇/zm, -20- 1290613 在其y方向(左右方向)之長度爲200 /zm;中央之十字 在y方向(左右方向)之長度爲l〇〇/zm;構成圖案之各 線寬爲1 0 V m。 攝影機A〜C之移動量誤差及攝影機A〜C之姿態 所造成之攝影機A〜C之視野位置之變動,係製成比 上的精度之比1 00 // m小很多。因此,藉由使用X方向 攝影機位置之指令値或測定値,即確定正在看基準標 之任一週期圖案,若拍攝基準標尺1 3,即可知道視野 準標尺1 3之圖案上之點(例如:距離視野中心最近的 圖案之中心)在以載台5作爲基準之座標系中之X座標 可以自此圖案上之點之X座標知道視野中心在以載台 爲基準之座標系中之X座標。 因y方向上之視野之變動也比1 0 0 // m小很多,所 若使載台5移動至既定之位置,即可將基準標尺13確 入攝影機A〜C之視野內,且可以自拍攝所得之基準 1 3之圖像知道視野中心此時之y座標。如此既求得之 中心之X座標及y座標,可用於求取測定對象處座標 的補正。 又,也能以攝影機A〜C之視野中至少1個移入般 隔,在基準標尺1 8之圖案以數字或圖形編碼追加其所 之座標之資訊,自拍攝所得的圖像直接讀取座標之値 此’不使用攝影機位置或載台位置之指令値或測定値 可以僅自拍攝所得之圖像求取視野中心之座標。 第4圖表示使用此位置測定裝置1來對基板1 2之 圖案 線之 變動 機械 上之 尺13 內基 十字 ,且 5作 •以, 實移 標尺 視野 之時 的間 在地 。如 ,也 測定 -21 - I29Q613, 對象處來進行之測定步驟之槪略。首先,於載台5上載置 基板12(步驟nl),如後所述執行測定(步驟n2),自載台5 回收基板12(步驟n3),結束。 其次,將步驟η 2中測定之詳細內容應用於幾個具體例 並加以說明。 第5圖表示使用攝影機Α來進行的身爲基板1 2上測定 對象處的基準標記P之座標之測定步驟,其表示在各步驟 1〜3載台與攝影機之位置關係,及處理之內容。 φ 在此,基準標記P之座標係指第2圖之十字標記p之 中心座標。十字標記P也簡稱爲點P。 在步驟1,移動攝影機移動機構,以使攝影機A朝X 方向移動,而成爲假定攝影機A之視野內可以涵蓋點p的 位置關係,而且,使載台5朝y方向移動,以使載台5與 攝影機A之位置關係爲第6圖所示之狀態a,且以攝影機A 拍攝基板1 2之點P。 攝影機A及載台5之移動較佳爲同時進行;但是,也 • 可以依序進行 又,以下之說明中,將就拍攝測定對象處或基準標尺 1 3的攝影機之移動加以說明;但是,也使其他不進行拍攝 之攝影機以不妨礙要拍攝之攝影機之移動的方式視必要情 況朝X方向移動。 在此步驟1,在以攝影機A拍攝假定點P存在之處, 點P也尙未移入視野中之情況下,使攝影機A及載台5作 細微移動,例如:如第9圖所示,分成8次拍攝包圍以斜 -22- I29Q613· 線表示之最初拍攝位置Z的區域,直到點p移入視野內爲 止。即便如此,仍無法拍攝點P,則進一步分成多次拍攝 其外側之區域,直到點P移入視野內爲止。 又,第9圖顯示例子:使載台5自以斜線表示之最初 拍攝位置Z朝y方向作細微移動1次,拍攝,因點p尙未 移入視野內,故再使攝影機A朝X方向作細微移動1次, 拍攝’點P移入了視野內。此外,也以假想線表示在第2 次之拍攝,點P尙未移入視野內之情況下拍攝位置之微動。 • 其次,在第5圖之步驟2,不移動攝影機移動機構, 保持拍攝點P後之原狀下,亦即,保持攝影機A靜止後之 狀態下’僅使載台5朝y方向移動,以使載台5與攝影機a 之位置關係爲第7圖所示之狀態b,且以攝影機A拍攝基 準標尺1 3。 在步驟3’藉由圖像處理及運算來算出點p之座標。 第8圖’係爲了說明利用此圖像處理及運算來算出點 P之座標,槪略表示拍攝點p後之視野、拍攝基準標尺i 3 Φ 後之視野與載台5之位置關係。 首先’處理拍攝點P所得之圖像,以求取點p在以第 8圖(a)所示之視野中心〇作爲原點之視野座標系中的座標 U1,y 1) 〇 其次’自拍攝點P後之狀態起不移動攝影機A,僅使 載台5移動,處理拍攝所得之基準標尺1 3之圖像,以求取 視野中心0在第8圖(b)所示之基準標尺拍攝時之載台座標 系的座標(X1,Y1)°此時,也使用X方向上之攝影機位置之 -23- 1290613 指令値或測定値,及y方向上之載台位置之指令値或測定 値’來求取視野中心〇之座標(XI,Yi)。亦即,因可以根 據指令値或測定値,來知道拍攝圖像內基準標尺1 3之圖案 上之點在載台座標系中之X,y方向之座標,故從此圖案與 視野中心0之位置關係,求取視野中心〇在載台座標系之 座標(XI,Y1)。 再者’取得來自線性編碼器之移動量之測定値△ y,以 作爲在拍攝點P之後到拍攝基準標尺1 3之前的載台5之移 • 動量。若已證實載台移動量之指令値一致於來自線性編碼 器之測定値△ y,則也可以取得該指令値來作爲載台5之 移動量。在此情況下,也就是說已間接取得來自線性編碼 器之載台5移動量之測定値。 第8圖(b)中既求得之視野中心〇在基準標尺拍攝時在 載台座標系之X座標X 1加上第8圖(a)中點P在視野座標 系之X座標X 1所得的値(X 1 + X 1 ),是點P在載台座標系之 X座標。 • 第8圖(b)中既求得之視野中心〇在基準標尺拍攝時在 載台座標系之y座標Y1加上載台移動量Ay以及第8圖(a) 中點P在視野座標系之y座標yl所得之値(Y1 + △ y + yl), 是點P在載台座標系之y座標。 又,若在測定載台5之移動量時判明載台5與基台3 之間之相對位置關係,即可求取身爲以基台3爲基準之測 定對象處的點P位置。 如上所述,須利用拍攝基準標尺1 3所得之圖像及載台 -24-[Technical Field] The present invention relates to a method and apparatus for measuring a position of a measurement target on a substrate, such as a glass substrate for a liquid crystal panel, and a position measurement using the same system. [Prior Art] In order to check the dimensional accuracy of the substrate, a measurement object such as a substrate is placed on a base or a moving stage, and the object to be measured is photographed by a camera that can move the object with respect to φ. The image obtained is taken to obtain the position of the measurement object. For example, Patent Document 1 discloses that a measurement target is placed on a fixed stage, and a measurement target is imaged by a camera mounted on a stage that moves in one direction. [Patent Document 1] JP-A-2003-286 1 1 [Description of the Invention] [Disclosure of the Invention] [Problems to be Solved by the Invention] • It is relatively easy to accurately measure or control the amount of movement of the base loading table; When the position of the field of view of the camera taken from above on the stage is measured, a large error occurs depending on the movement of the camera. The error in the position of the visual field is caused by the error of the amount of movement of the camera itself and by the change of the posture of the camera. The error in the position of the visual field caused by the change in the posture of the camera is caused by the change in the optical axis direction of the camera as the posture of the camera changes, and as a result, the position of the visual field on the measurement object changes. I29Q613 It is difficult to reduce the error of the camera's field of view position by mechanical precision. In particular, the error caused by the change in the attitude of the camera is sensitive even to the tilt of a little camera, so it is very difficult to sufficiently reduce the error. For example, if the distance between the camera and the object to be measured is 200 mm, the slope of the camera is only 1/1 〇〇〇, and the change in the position of the field of view on the object is 3 · 5 // m. It is difficult to avoid the occurrence of a change in the attitude of the camera every time the camera is moved, and this error cannot be tolerated when the high-precision measurement is required as in the case of inspecting the glass substrate of the liquid crystal panel. SUMMARY OF THE INVENTION An object of the present invention is to prevent an error in position measurement of an image of a camera caused by a movement error of a camera and a change in posture of a camera when measuring the position of the object on the measurement substrate. [Means for Solving the Problem] (1) The position measuring method of the present invention: a position measuring device having: a base; a stage that moves in the first direction on the base; a movement amount measuring device for moving the stage; a gantry fixed to the base; a camera moving mechanism provided on the gantry with a second direction orthogonal to the first direction as a movable direction; supported by the camera moving mechanism a camera that moves in the second direction above the base; and a reference scale that is mounted on the stage in a direction perpendicular to the direction in which the stage moves, and is used to capture the image after being captured by the camera. The information relating to the position of the camera's field of view is provided, and the substrate to be measured is placed on the stage, and any of the measurement target and the reference scale on the substrate is imaged by the camera, and the camera moving mechanism is moved without I29Q613. In the original state after the photographing, only the above-mentioned stage is moved, and the above-mentioned substrate is photographed by the camera to measure the pair. And the other of the reference scales, the amount of movement of the stage under the movement is measured by the movement amount measuring device, and the image of the measurement target and the image of the reference scale and the movement amount of the stage are used. To find the location of the measurement object. The "movement amount measuring device" is not limited to a device for directly measuring the amount of movement of the stage as in the case of a linear encoder, and may be a device for indirectly measuring the amount of movement of the stage Φ, for example, from the command of the amount of movement of the stage. The amount of movement of the device. Preferably, the "stand" is mounted on the base platform so as to span the moving area of the stage so that the camera supported by the camera moving mechanism equipped with the gantry can photograph the substrate or the reference scale placed on the stage from above. Since the camera is supported by the camera moving mechanism that is movable in the second direction and moves in the second direction, the camera moving mechanism can move the camera in the second direction, and does not move the camera moving mechanism. When the camera does not move, it remains as it is. # The reference scale is equipped on the stage, so the position information of the camera field of view provided in the image of the camera after the reference scale is taken becomes the information based on the position of the stage. Since the reference scale is provided along a direction perpendicular to the moving direction of the stage, that is, along the second direction in which the writing direction is the moving direction of the camera, the reference scale is captured at each moving position of the moving direction of the camera, that is, Get location information for the field of view. Preferably, the reference scale is for providing position information of the field of view associated with the first direction and the second direction. Moreover, the reference scale is preferably provided to provide the front I29Q613. In the pattern of the first direction and the second direction information, information for providing the coordinates of the two directions in the pattern may be added to the pattern. Three kinds of information are used in the position measuring method of the present invention. The first information used is the image of the reference scale. From this image, the position of the camera's field of view when the reference scale is taken can be obtained. The position of this field of view is the position of the reference scale when the reference scale is taken, that is, the position based on the position of the stage at that time. The position of the field of view is caused by an error in the amount of movement of the camera and a change in the posture of the camera. However, even if there is such a difference in the positional position error II, the error in the position of the field of view is obtained by using the position of the field of view obtained from the image of the reference scale image obtained by the imaging. Does not affect the position measurement results. The second information to be used is the amount of movement of the stage between the time when the reference scale is captured and when the measurement target is taken. When the first information and the second information are used, the position of the field of view at the time of shooting the measurement target based on the position of the stage when the reference scale is taken can be obtained. The third information to be used is an image of the measurement target. With this image, the position of the measurement target based on the field of view of the camera at the time of the measurement target can be obtained. Therefore, if all the information is used, the position of the measurement target based on the position of the stage when the reference scale is taken can be obtained. When the relative positional relationship between the stage and the base is determined by measuring the amount of movement of the stage, the position of the measurement target based on the base can be obtained by the position measuring method of the present invention. According to the position measuring method of the present invention, when the position of the measuring object is measured on the measuring substrate, the camera movement position error I29Q613 caused by the movement error of the camera and the posture change of the camera can not affect the position measurement by the shooting of the reference scale. result. Further, after the camera detects the measurement target on the substrate and the reference scale, the camera is not moved until the other of the measurement target and the reference scale on the substrate is photographed by the camera. In this state, the camera is relatively The base system is stationary, so that it is possible to prevent errors in the position of the camera during this period. Therefore, the measurement accuracy of the position at the measurement target is improved. (2) In one embodiment of the position measuring method of the present invention, the position measuring device is prepared, and a base φ plate to be measured is placed on the stage, and the measurement target on the substrate is imaged by the camera without moving. The camera moving mechanism moves the reference stage while the image is moved, and the camera moves the reference scale, and the amount of movement of the stage under the movement is measured by the movement amount measuring device. The image of the measurement target and the image of the reference scale and the amount of movement of the stage are obtained to obtain the position of the measurement target. In the position measuring method of the present embodiment, the reference scale is taken after the measurement target is taken. In this case, you can reverse this order and take a picture of the subject after taking the reference scale. However, in this case, the position of the substrate is shifted due to the in-plane rotation, or because of the subject. The reason for the low accuracy of the formation position may be that the measurement target is not found in the field of view after the stage is moved, contrary to the assumption. In this case, it is necessary to change the assumed position at which the measurement target is to be found. At the same time, when the position of the camera is moved, the error may occur due to the movement of the camera. Therefore, the method of capturing the reference scale first must be repeated from the shooting of the reference scale. On the other hand, in the position measurement method of 1290613 in which the reference scale is taken after the measurement target is taken, if the measurement target is not found in the field of view including the assumed position of the measurement target, then a little bit each time Any one or both of the stage and the camera are moved, and the position to be measured is searched for, and the position of the measurement target is captured, and the stage is moved without moving the camera, and the reference scale is photographed. Therefore, it is not necessary to retake the reference scale. (3) In the embodiment of the above (2), the position measuring device may be prepared, and a substrate to be measured may be placed on the stage, and the first measurement target on the substrate may be imaged by the 0 camera. In a state where the camera moving mechanism is not moved, the stage is first moved, the camera is photographed by the reference scale, and the first image of the reference scale is obtained, and the stage is measured by the movement amount measuring device. The second movement of the stage is performed without moving the camera moving mechanism, and the camera is photographed on the surface of the substrate on which the second measurement target is supposed to be imaged by the camera. When there is a second measurement target in the image, the # image is used as the image of the second measurement target; and if the second measurement target is not present in the captured image, the stage or the camera moving mechanism is used. The image is moved slightly and photographed, and the second movement amount of the stage is measured by the movement amount measuring device until the second measurement target is successfully captured. Alternatively, after the stage is slightly moved as described above, the amount of movement of the second movement amount plus the fine movement portion is measured by the movement amount measuring device as the second movement amount, and -10- 1290613 succeeds. When the second mechanism of the second measurement target is photographed, the second measurement T moves the camera moving mechanism, and moves in this state, and the second image of the reference scale is captured by the camera, and the movement amount measuring device is used. For the momentum, the first image of the first and second measurement targets, the second image of the first and second movements of the stage, and the position of the third movement measurement target of the stage are used. According to this embodiment, it is possible to use a position in which the measurement target is separated by a small movement direction of the carrier (4). In the above-described (2) embodiment, the position measuring device may have a camera. The first camera supported by the moving mechanism and the second camera moving mechanism moving mechanism and the second camera that is the second camera; and the direction in which the first and second camera stages move in the direction are separated, and the first substrate is the first When the camera captures the image and the second camera 1 and the second camera moving mechanism are photographed by the second camera, the first and second cameras respectively capture the reference scale to measure the movement of the stage under the movement and the first (2) The image of the measurement target, the first and the state when the camera is moved, and the third stage of the stage is measured by obtaining the reference scale to obtain the image of the third movement of the stage. The first scale of the reference scale amount and the amount of the baseline, and the base amount, to determine the first and second movements, to measure the two positions, to prepare the position measurement, and the first camera; and the camera 1 camera movement mechanism The field of view of the support is placed on the stage perpendicular to the stage as the first measurement target on the measurement substrate, and the stage is moved without moving, so that the first camera can be used by the measurement of the amount of movement. Shoot -11- I29Q613 separately. The first and second measurement targets are obtained by obtaining the first and second images of the reference scale and the movement amount of the stage. Preferably, the first and second cameras are supported by the gantry that is erected in a direction perpendicular to the moving direction of the stage by the first and second camera moving mechanisms, and that the moving area of the stage is traversed so that the first and second cameras can be secured. A field of view that is perpendicular to the direction of movement of the stage. The first and second cameras are used to capture the first and second measurement targets, and the first and second cameras are used to capture the reference scale. The first and second cameras are simultaneously performed. According to this embodiment, two cameras can be used to measure the position of two measurement objects separated in the direction perpendicular to the moving direction of the stage with a small movement of the stage. (5) In the embodiment of the above (2), the position measuring device may be provided, the position measuring device having the first camera moving mechanism and the second camera moving mechanism that can move independently of each other, and being moved by the first camera The first camera supported by the mechanism and the #2th camera supported by the second camera moving mechanism; and the fields of view of the first and second cameras are separated from each other in a direction perpendicular to the moving direction of the stage, and placed on the stage as a measurement The substrate of the target is photographed by the first camera at the first measurement target on the substrate, and the first camera movement mechanism is not moved, and the first camera is moved after the image capture, and the second camera is moved. The second measurement target on the substrate is photographed, and the first movement amount of the stage under the first movement is measured by the movement amount measuring device, and the first and second camera movement mechanisms are not moved. The second movement of the stage is performed, and the reference scale is photographed by each of the first -12-1290613 and the second camera, and the second movement of the stage under the second movement is measured by the movement amount measuring device. The first and second images of the reference scale are captured by the first and second cameras using the images of the first and second measurement targets, and the first and second movement amounts of the stage are used. The position of the first and second measurement targets is obtained. When moving the second camera moving mechanism to change the visual field position of the first camera, it is preferable not to move the first camera moving machine φ during the shooting from the first measurement target to the second measurement target. The second camera movement mechanism is also not moved. Therefore, in order to move the second camera moving mechanism in order to capture the second measurement target by the second camera, it is preferable to move the second camera moving mechanism before the first camera is photographed by the first camera. According to this embodiment, two cameras can be used to measure the position of two measurement targets at arbitrary positions on the substrate with a small movement of the stage. In the present embodiment, the first camera, the second camera, or another camera may be used between the first measurement target (first imaging) and the second measurement target (second imaging). To shoot other measurement objects. In this case, the cumulative movement amount of the stage from the first imaging to the second imaging (the distance from the stage position after the first imaging to the stage position after the second imaging) is the first of the stage. The amount of movement. In this embodiment, a position measuring device including a plurality of cameras such as a third camera and a fourth camera may be used to support an individual camera moving mechanism, and the number of cameras may be sequentially captured while moving the stage. At the corresponding measurement target, the shooting of the reference scale by each camera is performed in the common stage position of -13-1290613. In this case, if two or more of the measurement targets are separated in the moving direction of the stage, the measurement target can be photographed by a common camera, so that it is possible to measure more than the number of cameras. Determine the position of the object. Further, when two or more of the measurement target portions are separated in the direction perpendicular to the movement direction of the stage, the measurement target positions can be taken at the common stage position. Obviously, if the camera moving mechanism is moved, the number of measurement targets that can be measured is not limited regardless of the number of cameras. However, during the period in which the camera moving mechanism is moved after the camera moving mechanism is moved, the reference scale is photographed once by the camera supported by the camera moving mechanism. (6) The position measuring method according to any one of (1) to (5), wherein the substrate may be provided with a pattern that can be photographed, and the measurement target on the substrate is at least two selected from the pattern. The reference mark further obtains the position and posture of the pattern by using the position of at least two of the reference marks obtained. (7) The position measuring method according to any one of (1) to (5), wherein the substrate may be provided with a pattern that can be imaged, and the measurement target on the substrate is the first point selected from the pattern. And the second point, the distance between the first point and the second point is further obtained by using the positions of the first point and the second point. (8) In the position measuring method according to any one of (1) to (5), the substrate may be provided with a pattern that can be imaged, and the measurement target on the substrate is the first selected from the pattern. For the 2nd, 3rd, and 4th points, use the -14-1290613 to find the positions of the 1st, 2nd, 3rd, and 4th points, and to connect the 1st and 2nd points and the 3rd point. The angle with the 4th point. Points 2 and 3 can also be a common point. According to this embodiment, it is possible to obtain a distortion-related information by selecting a measurement object under the assumption that two lines are orthogonal to each other under the assumption that the two lines are orthogonal to each other, so that sensitive deformation information can be obtained. (9) Position measurement of the present invention The device has: a base; φ the base is moved in the first direction; the movement measuring device uses the amount of movement of the stage; the gantry is fixed to the base; the camera is equipped with the gantry to the first direction a second direction of the orthogonal direction; the camera is supported by the camera moving mechanism and moves in the second direction above; and the reference scale is placed on the stage along the moving direction of the loading table, after being photographed 'Use to provide camera field of view information in the captured image. # According to the position measuring device of the present invention, the movement amount error of the camera and the posture change of the camera can be made by the reference scale without affecting the position measurement result. Further, since the camera is stationary with respect to the base during the measurement target and the base period on the imaging substrate, it is possible to prevent an error in the position of the camera visual field. Therefore, the accuracy of the measurement target is improved. (1) An embodiment of the position measuring apparatus of the present invention seeks to obtain information on a straight line. In particular, the stage is used to measure the front p-motion mechanism. As the movable base is directly photographed by the camera, the position of the quasi-scale is determined during the period. - 1290613. The reference scale is disposed on both sides of the stage in which the stage is moved across the area on the stage on which the substrate is to be placed. According to this embodiment, if the positional relationship between the two side reference scales is known, any one of the reference scales can be used. Therefore, by appropriately selecting the reference scale to be used, the amount of movement of the stage can be reduced. (11) The position measuring system of the present invention includes the position measuring device according to (9) or (10) above, and a control device capable of transmitting information to each other after being connected to the position measuring device, wherein the control device is provided to execute a control program In the computer of Φ, the control program includes the step of: photographing the target object and the reference scale on the substrate placed on the stage of the position measuring device by the camera, and moving the camera moving mechanism without holding the camera moving mechanism In the original state after the photographing, only the stage is moved, and the other of the measurement target and the reference scale on the substrate is imaged by the camera, and the movement of the stage under the movement is measured by the movement amount measuring device. The amount is obtained by using the image of the measurement target and the image of the reference scale and the amount of movement of the stage to determine the position of the measurement target. • According to the position measuring system of the present invention, when the position of the object is measured on the measuring substrate, by the shooting of the reference scale, the error of the movement amount of the camera and the position of the camera visual field caused by the change of the posture of the camera can be made to not affect the position. The measurement results. Further, since the camera is stationary with respect to the base during the measurement of the target on the substrate and the reference scale, it is possible to prevent an error in the position of the field of view of the camera during this period. Therefore, the measurement accuracy of the position at the measurement target is improved. [Effect of the Invention] -16- I29Q613 According to the present invention, when the position of the measurement target on the substrate is measured, the camera movement can be caused by the movement amount error of the camera and the posture change of the camera by the shooting of the reference scale. The position error does not affect the position measurement result, and the camera is stationary with respect to the base during the measurement target on the substrate and the reference scale, so that it is possible to prevent an error in the camera visual field position during this period. Therefore, the measurement accuracy of the position at the measurement target is improved. [Embodiment] # [Best Mode for Carrying Out the Invention] Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Fig. 1 is a perspective view showing a schematic configuration of a position measuring system according to an embodiment of the present invention; and Fig. 2 is a plan view showing a position measuring device. As shown in Fig. 1, the position measuring system of the present embodiment includes a position measuring device 1 and a control device 2 connected to the position measuring device 1 so that information can be transmitted to each other. Further, the control device 2 has a computer for executing a control program for controlling the position measuring device 1. # Position measuring device 1 is provided with a base 3 made of stone such as granite; a stage 5 which is movable along one of the rails 4 provided thereon; and is mounted on the base 3 so as to straddle the stage 5 a gantry table 6 at an upper fixed position; a plurality of camera moving mechanisms not shown in the gantry 6, and a plurality of cameras (three in the present embodiment) supported by the camera moving mechanisms A to C0 The rectangular plate-shaped stage 5 can be moved -17-I29Q613 in the y direction (the left-right direction of the second drawing) of the first direction by a driving mechanism such as a linear motor (not shown). move. Each of the cameras A to C can be moved independently of each other in the X direction by using the camera moving mechanism in the X direction (the upper and lower directions in the second drawing) which is the second direction orthogonal to the first direction as the movable direction. . A linear scale 10 extending in the y direction of the moving direction of the stage 5 is provided on the base 3, and an encoder (not shown) that moves integrally with the stage 5 is provided on the lower surface of the stage 5. Take the lead. The linear encoder is constructed by a linear scale 1 〇 and an encoder read head, and is used as a movement amount measuring device for measuring the amount of movement of the stage 5 in the y direction. φ linear scale 1 〇 and encoder read head are provided in two sets, so that two linear encoders are formed. 'The linear encoders are used to measure the movement of the front side and the opposite side of the first picture on the stage $. . Each of the encoder reading heads is provided with a light projecting unit and a light receiving unit, and the light receiving unit receives the reflected light that is emitted from the light projecting unit and is modulated by the linear scale 1 , to obtain a pulse corresponding to the amount of movement of the stage 5 . Signal. In addition, an origin pattern is provided at each of the linear scales 10, so that the origin signal of the stage position can also be obtained. The reason why the linear scale 10 is set to two is to correct the error in the amount of movement of the stage caused by the deflection of the stage Φ 5 (return in the horizontal plane). A linear interferometer can be replaced with a laser interferometer or other known motion meter. A laser displacement meter 1 opposed to the side surface of the stage 5 is provided on the base 3, whereby the displacement of the side surface of the stage 5 is measured by the laser displacement meter 1 . The laser displacement meter 1 is provided with a light projecting optical system for irradiating a laser beam toward an object, and a light receiving optical system for receiving light reflected from the object by the position detecting element through the light receiving lens, -18-1290613, The projection optical axis and the light receiving optical axis intersect at a predetermined crossing angle in the vicinity of the object, and the beam spot generated by imaging the position detecting element by the spot of the laser beam on the object is used. The position changes after the distance to the object changes, and the principle of the triangulation is used to obtain the amount of change in the distance or distance to the object. The displacement measurement result obtained by the laser displacement meter 1 is used as a measure of the amount of displacement of the stage 5 in the X direction caused by the movement of the stage 5, and is used as a measure for being placed on the stage 5. On the substrate 1 2 of the object • The position measurement result at the measurement target. Figs. 1 and 2 show a laser displacement meter 1 1. The following figure omits the illustration of the laser displacement meter 1 1. The stage 5 placed on the substrate 1 2 to be measured is made of stone such as granite as in the base 3, and the stage 5 is provided with a positioning for positioning the substrate 12 by abutment. The pin is sucked from the substrate 12 to make the substrate 12 adhere to the adsorption hole of the stage 5. Further, on one end of the stage 5 (the left end of the figure), a reference scale 13 extending in the X direction perpendicular to the moving direction (y direction) of the stage 5 is provided, and the reference scale is used for taking a picture. In the image, information relating to the visual field positions of the cameras A to C after being photographed by the respective cameras A to C is provided. The substrate 12 is, for example, a glass substrate for a liquid crystal panel, and has a size of 720 mm in the X direction and 920 mm in the y direction. A reference mark and a wiring pattern (not shown) are formed on the substrate 12 by etching of a metal film. The cross marks P, Q, R, and S in Fig. 2 are fiducial marks. Must be ±0. in the whole domain of this substrate 12. 5 / m precision position measurement. Each of the camera moving mechanisms provided in the gantry 6 is configured to move the cameras -19 to 1290613 in the direction of the cymbal to capture the substrate 1 mounted on the stage 5. This camera moving mechanism has a linear encoder, and the linear encoder is used to measure the amount of movement of each of the cameras A to C in the x direction, and each of the cameras A to C is moved to the χ coordinate indicated by the control device 2. Due to the error in the amount of movement of the camera, it is corrected by the shooting of the reference scale 13. Therefore, the linear encoder can also use a coarse linear encoder with a low decomposition energy such as 1 V m. Each of the cameras A to C has an objective lens as a microscope and has a 2 > CCD imaging element. The shooting magnification can be changed by the replacement of the objective lens. The size of the field of view on the substrate 12 when adjusted to the highest magnification is 144/zm in the 第 direction of Fig. 2 and 110//m in the y direction. The control device 2 includes a keyboard and a display, and can immediately transmit a command to the position measuring device 1, or observe an image taken by the position measuring device 1, or input a program for controlling the position measuring device 1. The program for controlling the position measuring device 1 can also be downloaded from the outside via the network. Fig. 3 is an enlarged view showing a portion of the reference scale 13 in Fig. 2, the direction of the second figure (up and down direction) corresponds to the upper direction of the third figure, and the y direction of the second figure (left and right direction) corresponds to The left and right direction of Figure 3. This reference scale 13 is made of glass such as soda glass. In this embodiment, a repeating pattern having a period of l 〇〇 / / m is formed in the χ direction (up and down direction). This repeating pattern is a pattern in which the cross pattern is disposed in the center of the horizontally long rectangular pattern and is connected to the upper and lower sides of the rectangular pattern, and is not connected to the left and right sides. The length of the rectangular pattern in the χ direction (up and down direction) is l〇〇/zm, the length of -20-1290613 in the y direction (left and right direction) is 200 /zm; the center cross is in the y direction (left and right direction) The length is l〇〇/zm; the line width constituting the pattern is 10 Vm. The movement amount errors of the cameras A to C and the positions of the cameras A to C caused by the positions of the cameras A to C are much smaller than the precision of the ratio of 100 00 // m. Therefore, by using the command of the X-direction camera position or measuring 値, it is determined that any cycle pattern of the reference mark is being viewed, and if the reference scale 13 is photographed, the point on the pattern of the visual field scale 13 can be known (for example : The center of the pattern closest to the center of the field of view. The X coordinate in the coordinate system based on the stage 5 can be known from the X coordinate of the point on the pattern. The X coordinate of the center of the field in the coordinate system based on the stage is known. . Since the change of the field of view in the y direction is also much smaller than 1 0 0 // m, if the stage 5 is moved to a predetermined position, the reference scale 13 can be confirmed into the field of view of the cameras A to C, and can be self- The image of the reference 13 obtained is the y coordinate of the center of the field of view. The X coordinate and the y coordinate of the center thus obtained can be used to obtain the correction of the coordinates of the measurement object. Further, at least one of the fields of view of the cameras A to C can be moved in as much as possible, and the coordinates of the coordinates of the coordinates of the reference scale 18 are added by digital or graphic coding, and the coordinates are directly read from the captured image.値If you don't use the camera position or the position of the stage, you can determine the coordinates of the center of the field from the captured image. Fig. 4 is a view showing the use of the position measuring device 1 to change the pattern line of the substrate 1 to the inner cross of the ruler 13 on the machine, and to make the position of the scale of the scale to be in the ground. For example, -21 - I29Q613 is also measured, and the measurement procedure performed by the object is omitted. First, the substrate 12 is placed on the stage 5 (step n1), and measurement is performed as described later (step n2), and the substrate 12 is recovered from the stage 5 (step n3), and the process ends. Next, the details of the measurement in the step η 2 are applied to a few specific examples and explained. Fig. 5 is a view showing a measurement procedure of the coordinates of the reference mark P at the measurement target on the substrate 12 by using the camera ,, and shows the positional relationship between the stage and the camera in each of steps 1 to 3, and the contents of the processing. φ Here, the coordinate of the reference mark P refers to the central coordinate of the cross mark p of Fig. 2. The cross mark P is also simply referred to as a point P. In step 1, the camera moving mechanism is moved to move the camera A in the X direction, and it is assumed that the positional relationship of the point p can be covered in the field of view of the camera A, and the stage 5 is moved in the y direction so that the stage 5 is moved. The positional relationship with the camera A is the state a shown in Fig. 6, and the point P of the substrate 1 is taken by the camera A. The movement of the camera A and the stage 5 is preferably performed simultaneously; however, it can also be performed in sequence, and in the following description, the movement of the camera at the measurement target or the reference scale 13 will be described; however, The other cameras that do not perform the shooting are moved in the X direction as necessary, without hindering the movement of the camera to be photographed. In this step 1, in the case where the camera A takes the assumed point P, and the point P is not moved into the field of view, the camera A and the stage 5 are slightly moved, for example, as shown in FIG. The 8 shots surround the area of the initial shooting position Z indicated by the oblique -22-I29Q613· line until the point p moves into the field of view. Even if the point P cannot be taken, the area outside the film is further divided into a plurality of times until the point P moves into the field of view. Further, Fig. 9 shows an example in which the stage 5 is slightly moved one by one from the initial photographing position Z indicated by oblique lines to the y direction, and the photographing is performed because the point p is not moved into the field of view, so that the camera A is made to move toward the X direction. Move slightly 1 time, shooting 'P is moved into the field of view. In addition, the imaginary line indicates the micro-motion of the shooting position in the case of the second shot, and the point P尙 is not moved into the field of view. • Next, in step 2 of Fig. 5, the camera moving mechanism is not moved, and the original position of the shooting point P is maintained, that is, in a state where the camera A is kept stationary, 'only the stage 5 is moved in the y direction, so that The positional relationship between the stage 5 and the camera a is the state b shown in Fig. 7, and the reference scale 13 is photographed by the camera A. In step 3', the coordinates of the point p are calculated by image processing and calculation. Fig. 8 is a view for explaining the coordinates of the point P by the image processing and calculation, and schematically shows the visual field after the photographing point p and the positional relationship between the field of view after the imaging scale i 3 Φ and the stage 5. First, 'process the image obtained by the shooting point P to find the point U in the coordinate system of the field of view with the center of the field of view shown in Fig. 8(a) as the origin U1, y 1) 〇 second self-shooting After the point P, the camera A is not moved, and only the stage 5 is moved, and the image of the reference scale 13 obtained by the shooting is processed to obtain the center of view 0 when the reference scale shown in Fig. 8(b) is taken. The coordinate of the stage coordinate system (X1, Y1) ° At this time, the camera position of the camera in the X direction is also used -23-1290613 command 値 or measurement 値, and the position of the stage position in the y direction 値 or measurement 値 ' To find the coordinates of the center of vision (XI, Yi). That is, since the coordinates on the pattern of the reference scale 13 in the captured image in the X, y direction of the stage coordinate system can be known according to the command 値 or the measurement 値, the position from the pattern and the center of the field of view 0 For the relationship, find the coordinates of the center of the field (XI, Y1). Further, the measurement 値 Δ y from the movement amount of the linear encoder is taken as the movement amount of the stage 5 before the photographing point scale 13 after the photographing point P. If it has been confirmed that the command of the stage movement amount coincides with the measurement 値 Δ y from the linear encoder, the command 値 can also be obtained as the movement amount of the stage 5. In this case, that is, the measurement of the amount of movement of the stage 5 from the linear encoder has been indirectly obtained. The center of the field of view obtained in Fig. 8(b) is obtained from the X coordinate X 1 of the stage coordinate system and the point P of the eighth figure (a) in the coordinate coordinate system of the X coordinate X 1 at the reference scale. The 値 (X 1 + X 1 ) is the X coordinate of the point P in the coordinate system of the stage. • The center of the field of view obtained in Fig. 8(b) is the y coordinate Y1 plus the movement amount Ay of the stage coordinate system and the point P of the eighth figure (a) in the field of view coordinate system when the reference scale is taken. The y (y1 + Δ y + yl) obtained by the y coordinate yl is the y coordinate of the point P in the coordinate system of the stage. Further, when the relative positional relationship between the stage 5 and the base 3 is determined by measuring the amount of movement of the stage 5, the position of the point P at the measurement target based on the base 3 can be obtained. As mentioned above, the image obtained by the shooting reference scale 13 and the stage must be used -24-
12906 B 5之移動量以及拍攝點P所得之圖像這3種資訊,來求取 點P之座標(位置)。 可以藉由這3種資訊中身爲第1資訊的拍攝基準標尺 1 3所得之圖像,如上所述般求取在基準標尺拍攝時攝影機 A視野之位置(X 1,Y 1)。此視野之位置是基準標尺1 3在基 準標尺拍攝時之位置,亦即,以載台5當時之位置作爲基 準的位置。雖然攝影機A之移動量之誤差以及攝影機A之 姿態之變動導致視野之位置產生誤差,但是即便有這樣的 φ 視野位置誤差,由於利用自拍攝所得之基準標尺1 3之圖像 既求得之視野位置(X 1,Y 1 ),故視野位置之誤差不會影響位 置測定結果。 亦即,即便攝影機之移動量誤差及姿態變動已導致誤 差產生,仍可以藉著拍攝載台5上之基準標尺13,自與此 視野內基準標尺1 3之圖案間之位置關係來求取視野位置 之座標(X 1,Y 1),再利用此座標(X 1,Y 1),來排除視野位置 之誤差對位置測定結果的影響。 # 若使用身爲第2資訊的載台5在基準標尺拍攝時與點 P拍攝時之間之移動量Ay,以及身爲第1資訊的視野位置 之座標(X 1,Y 1 ),即可求取在點P拍攝時以載台5在基準標 尺拍攝時之位置作爲基準的視野位置。 再者,可以藉由身爲第3資訊的拍攝點p所得之圖像, 如上所述般求取以點P拍攝時攝影機A之視野作爲基_白勺 點P ill置(xl,yl)。因此’可以使用全部資訊,來求取以載 台5在基準標尺拍攝時之位置作爲基準的點p位置(χ丨+ -25- I29Q613. xl,Yl + Δ y + yl) 〇 如此,在測定基板12上身爲測定對象處之點P位置 時,可以藉著拍攝基準標尺13,使攝影機A之移動量誤差 及攝影機A之姿態變動所造成之攝影機視野位置誤差不影 響位置測定結果。而且,因在拍攝基板1 2上之點P及基準 標尺1 3之期間,攝影機A相對基台3係靜止著,故在此期 間,可以防止攝影機A之視野位置之誤差產生。因此,身 爲測定對象處之點P位置之測定精度使提高。 φ 上述第5圖之位置測定方法中,已經先拍攝身爲測定 對象處之點P,再拍攝基準標尺1 3,但也可以考慮將此順 序顛倒,先拍攝基準標尺13之後,再拍攝點P,不過,在 此情況下,有時由於基板1 2之載置姿態在面內旋轉偏移, 或拍攝對象之形成位置之精度低等,與假定不同地,在載 台移動後之視野內找不到點P,此時,如上所述般,如第9 圖所示,必須變更尋找點P的假定位置。 在因此而移動了攝影機A位置之情況下,移動導致攝 Φ 影機A因移動量誤差及姿態變動而產生視野位置之誤差, 故在先拍攝基準標尺1 3之方法中,必須再度從基準標尺;[3 之拍攝開始做。相對於此,在先拍攝點P之後再拍攝基準 標尺1 3的方法中,在涵蓋點p之假定位置的視野內找不到 點P之情況下,每次一點點地移動載台5及攝影機A中之 任一者或兩者,搜尋點P,自拍攝到點p之位置起在不移 動攝影機A之狀態下僅移動載台5,拍攝基準標尺13即可, 故不必重新拍攝基準標尺1 3。 -26 - 1290613 第l〇圖,係表示使用攝影機A來進行基板12之基準 標記P、Q、R、S之座標及相關尺寸以及角度的測定步驟。 點P、Q及點R、S如第2圖所示分別是2個在載台5 之移動方向分開的測定對象處,以點P、Q及點R、S之順 序來進行拍攝。 首先’與上述第5圖同樣地,在步驟1,假設爲第6 圖之狀態a,以攝影機A拍攝作爲第1測定對象處之點p ; 在步驟2 ’不移動攝影機移動機構,亦即,不使攝影機a 朝X方向移動,僅使載台5朝y方向移動,進行第1移動, 假設爲第7圖之狀態b,以攝影機A拍攝基準標尺13,以 取得基準標尺13之第1圖像。 其次,在步驟3,不移動攝影機移動機構,亦即,不 使攝影機A朝X方向移動,僅使載台5朝y方向移動,進 行第2移動,使載台5與攝影機A之位置關係爲第1 1圖所 示之狀態c,且以A拍攝身爲第2測定對象處之點Q。 此時,在攝影機A之視野中沒有點Q之情況下,與前 面使用第9圖就點P加以說明之情況同樣地,使攝影機A 及載台5做細微移動,搜尋點Q,並予以拍攝。 在搜尋此點Q時,使攝影機A朝X方向做細微移動並 拍攝點Q之後,移到步驟4,僅使載台5朝y方向移動, 進行第3移動,使載台5與攝影機A之位置關係爲第12圖 所示之狀態b’ ,且以攝影機A拍攝基準標尺13,以取得 基準標尺1 3之第2圖像,移到步驟5。 又,在點Q之搜尋時,使載台5朝y方向做細微移動, -27 - 1290.613, 拍攝點Q之後,使上述第2移動之移動量(第2移動量)加 上微動部分所得之累積移動量爲第2移動量。 在上述步驟3,在攝影機A之視野中存在點Q,不必 搜尋之情況下,或是在已進行搜尋,但未使攝影機A做細 微移動之情況下,不移動攝影機A,保持在步驟2拍攝基 準標尺1 3後之狀態,故跳過以攝影機A拍攝基準標尺1 3 之上述步驟4,移到步驟5。 在載台5之移動方向分開的點P、Q之座標,係在後述 • 之步驟9中被算出。 其次,對於點R、S,也與點P、Q同樣地,在步驟5, 使攝影機A朝X方向移動,並且使載台5朝y方向移動, 使載台5與攝影機A之位置關係爲第1 3圖所示之狀態d, 且以攝影機A拍攝作爲第1測定對象處之點R。 其次,在步驟6,不使攝影機A朝X方向移動,僅使 載台5朝y方向移動(第1移動),使載台5與攝影機A之 位置關係爲第1 4圖所示之狀態e,且以攝影機A拍攝基準 _ 標尺1 3。 其次,在步驟7,不使攝影機A朝X方向移動,僅使 載台5朝y方向移動(第2移動),使載台5與攝影機A之 位置關係爲第1 5圖所示之狀態f,且以攝影機A拍攝點S。 此時,在攝影機A之視野中沒有點s之情況下,與上述之 第9圖同樣地,使攝影機A及載台5做細微移動,搜尋點 S,並予以拍攝。 在搜尋此點S時,使攝影機A朝X方向做細微移動之 -28 - !29〇613 後,移到步驟8,僅使載台5朝y方向移動(第 載台5與攝影機A之位置關係爲第1 6圖所示之 以攝影機A拍攝基準標尺1 3,移到步驟9。 又,在點S之搜尋時,使載台5朝y方向做 拍攝點Q之後,使上述第2移動之移動量(第: 上微動部分所得之累積移動量爲第2移動量。 在上述步驟7,若攝影機A之視野中存在點 尋,或是已進行搜尋,但未使攝影機A做細微 # 移動攝影機A,保持在步驟6拍攝基準標尺13 故跳過以攝影機A拍攝基準標尺1 3之上述步驟 驟9。 在步驟9,如以下所述般算出點P、Q之座 在上述步驟3,若攝影機A之視野中存在點Q, 則使用利用攝影機A所得之點P、Q拍攝圖像 機A所得之基準標尺13之第1圖像,以及載台 動量及第2移動量,與上述之第8圖同樣地算技 # 座標。 此外,在上述步驟3,在攝影機A之視野中 時,進行點Q之搜尋,此時,使載台5朝y方 動,拍攝點Q之後,使上述第2移動量加上微: 之累積移動量爲第2移動量,算出點P、Q之座 再者,在上述步驟3,在攝影機A之視野中 時,進行點Q之搜尋,此時,使攝影機A朝X 移動,拍攝點Q之後,使用利用攝影機A所得The three kinds of information of the amount of movement of 12906 B 5 and the image obtained by shooting point P are used to find the coordinates (position) of point P. The image obtained by the photographing reference scale 13 which is the first information among the three types of information can be obtained as described above (X 1, Y 1) at the viewpoint of the camera A at the time of the reference scale shooting. The position of this field of view is the position of the reference scale 13 when the reference scale is taken, that is, the position based on the position of the stage 5 at that time. Although the error of the movement amount of the camera A and the change of the posture of the camera A cause an error in the position of the visual field, even if there is such a φ visual field position error, the image obtained by using the image of the reference scale 13 obtained by the self-photographing is obtained. The position (X 1, Y 1 ), so the error in the position of the field of view does not affect the position measurement result. That is, even if the error of the movement of the camera and the change of the attitude have caused an error, the positional relationship between the pattern of the reference scale 13 in the field of view can be obtained by the reference scale 13 on the photographing stage 5. The coordinate of the position (X 1, Y 1), and then use this coordinate (X 1, Y 1) to exclude the influence of the error of the visual field position on the position measurement result. # If you use the movement amount Ay between the time when the stage 5 is the second information and the point P is taken, and the coordinate (X 1, Y 1 ) of the field of view position of the first information, The visual field position at which the position of the stage 5 is photographed on the reference scale is taken as a reference at the time of point P shooting. Further, by the image obtained as the photographing point p of the third information, the field of view of the camera A at the point P can be obtained as the base point P ill (xl, yl) as described above. Therefore, 'all the information can be used to obtain the point p position (χ丨+ -25- I29Q613. xl, Yl + Δ y + yl) based on the position of the stage 5 at the time of the reference scale shooting. When the upper body of the substrate 12 is at the point P of the measurement target, the positional measurement result of the camera can be prevented from affecting the position measurement result caused by the movement amount error of the camera A and the posture change of the camera A by the imaging reference scale 13. Further, since the camera A is stationary with respect to the base 3 while the point P on the substrate 12 and the reference scale 13 are being photographed, it is possible to prevent an error in the visual field position of the camera A during this period. Therefore, the measurement accuracy of the position P at the point of measurement is improved. φ In the position measurement method of Fig. 5 above, the point P at the measurement target is photographed first, and the reference scale 13 is photographed. However, it is also conceivable to reverse this order. After the reference scale 13 is photographed first, the point P is taken again. However, in this case, the mounting position of the substrate 12 may be shifted in-plane, or the accuracy of the position at which the object is formed may be low, and the assumption may be made in the field of view after the stage is moved. When the point P is less than this, as described above, as shown in Fig. 9, it is necessary to change the assumed position of the search point P. When the position of the camera A is moved, the movement causes the camera A to have an error in the position of the field of view due to the movement amount error and the posture change. Therefore, in the method of first capturing the reference scale 13, it is necessary to re-take the reference scale. ;[3 Shooting starts to do. On the other hand, in the method of capturing the reference scale 13 after the point P is first captured, the stage 5 and the camera are moved little by little each time the point P is not found in the field of view covering the assumed position of the point p. In either or both of the search points P, since the position of the point p is photographed, only the stage 5 is moved without moving the camera A, and the reference scale 13 can be photographed, so that it is not necessary to retake the reference scale 1 3. -26 - 1290613 The first diagram shows the steps of measuring the coordinates of the reference marks P, Q, R, and S of the substrate 12 and the relative dimensions and angles using the camera A. As shown in Fig. 2, the points P and Q and the points R and S are two measurement targets separated in the moving direction of the stage 5, and are photographed in the order of points P, Q and points R and S. First, in the same manner as in the fifth embodiment described above, in step 1, it is assumed that the state a of the sixth figure is taken, and the point A as the first measurement target is captured by the camera A; in step 2, the camera moving mechanism is not moved, that is, When the camera a is moved in the X direction, only the stage 5 is moved in the y direction, and the first movement is performed. As a state b of the seventh drawing, the camera A is photographed with the reference scale 13 to obtain the first figure of the reference scale 13. image. Next, in step 3, the camera moving mechanism is not moved, that is, the camera A is moved in the y direction without moving the camera A in the X direction, and the second movement is performed, so that the positional relationship between the stage 5 and the camera A is In the state c shown in Fig. 1, the point Q at the second measurement target is taken by A. In this case, when there is no point Q in the field of view of the camera A, the camera A and the stage 5 are moved slightly, and the point Q is searched and photographed in the same manner as the case where the point P is described using the ninth figure. . When searching for this point Q, the camera A is moved slightly in the X direction and the point Q is photographed. Then, the process proceeds to step 4, and only the stage 5 is moved in the y direction to perform the third movement, so that the stage 5 and the camera A are moved. The positional relationship is the state b' shown in Fig. 12, and the reference scale 13 is photographed by the camera A to acquire the second image of the reference scale 13 and the process proceeds to step 5. Further, at the time of the search of the point Q, the stage 5 is slightly moved in the y direction, -27 - 1290.613, and after the shooting point Q, the movement amount (the second movement amount) of the second movement is added to the micro-motion portion. The cumulative movement amount is the second movement amount. In the above step 3, there is a point Q in the field of view of the camera A. If there is no need to search, or if the search has been performed, but the camera A is not moved slightly, the camera A is not moved, and the shooting is performed in step 2. Since the state of the reference scale 13 is after, the above step 4 of taking the reference scale 1 3 by the camera A is skipped, and the process proceeds to step 5. The coordinates of the points P and Q which are separated in the moving direction of the stage 5 are calculated in step 9 which will be described later. Next, similarly to the points P and S, in the same manner as the points P and Q, in step 5, the camera A is moved in the X direction, and the stage 5 is moved in the y direction, so that the positional relationship between the stage 5 and the camera A is In the state d shown in Fig. 3, the point R at the first measurement target is captured by the camera A. Next, in step 6, the camera A is not moved in the X direction, and only the stage 5 is moved in the y direction (first movement), and the positional relationship between the stage 5 and the camera A is the state e shown in FIG. And take the camera A to take the reference _ scale 1 3 . Next, in step 7, the camera A is moved in the y direction without moving the camera A in the X direction (second movement), and the positional relationship between the stage 5 and the camera A is the state f shown in Fig. 15. And the point S is taken by the camera A. At this time, when there is no point s in the field of view of the camera A, the camera A and the stage 5 are finely moved in the same manner as in the above-described ninth drawing, and the point S is searched for and photographed. When searching for this point S, make the camera A make a slight movement of -28 - !29〇613 in the X direction, then move to step 8, and only move the stage 5 in the y direction (the position of the stage 5 and the camera A) The relationship is that the camera A is photographed with the reference scale 13 as shown in Fig. 16. The process proceeds to step 9. Further, at the time of the search of the point S, the second movement is performed after the stage 5 is made to the photographing point Q in the y direction. The amount of movement (the cumulative movement amount obtained by the upper micro-motion part is the second movement amount. In the above step 7, if there is a point search in the field of view of the camera A, or the search has been performed, but the camera A is not made to make a fine # move The camera A keeps the reference scale 13 in step 6, so skips the above-mentioned step 9 of capturing the reference scale 13 by the camera A. In step 9, the points P and Q are calculated as described below in the above step 3. When there is a point Q in the field of view of the camera A, the first image of the reference scale 13 obtained by capturing the image machine A using the points P and Q obtained by the camera A, and the stage momentum and the second movement amount are compared with the above. Figure 8 is the same as the technique # coordinate. In addition, in the above step 3, in the field of view of camera A At this time, the search for the point Q is performed. At this time, the stage 5 is moved toward the y, and after the point Q is captured, the second movement amount is added: the cumulative movement amount is the second movement amount, and the points P and Q are calculated. In addition, in step 3 above, in the field of view of camera A, the search for point Q is performed. At this time, camera A is moved toward X, and after shooting point Q, the use of camera A is used.
3移動),使 狀態e’且 細微移動, i移動量)加 i S,不必搜 移動,則不 後之狀態, 丨8,移到步 標。亦即, 不必搜尋, 、利用攝影 5之第1移 i點P、Q之 未存有點Q 向做細微移 動部分所得 :標。 未存有點Q 方向做細微 =之點P、Q -29- 1290613^ 拍攝圖像、基準標尺13之第1及第2圖像,以及載台5之 第1、第2及第3移動量,來算出點P、Q之座標。 以同樣之方式也算出點R、S之座標。 在步驟10,自各算出之點之座標,來算出各基準標記 間之尺寸,以及連接各基準標記間之直線中之2條直線所 成的角度。 例如算出自基準標記P、Q之各座標到基準標記P、Q 間之距離(尺寸),或例如算出連接基準標記P、Q之直線與 φ 連接基準標記Q、S之直線所成的角度,亦即,算出正交度。 如此,由於算出基板12上之基準標記P、Q、R、S間 之尺寸或連接此等標記之直線所成的角度,故可以把握基 板上圖案之變形、正交度。 第17圖表示使用作爲第1、第2攝影機之攝影機A、B 來測定基板1 2之基準標記S、Q之座標的步驟之圖。 作爲第1、第2測定對象處之點S、Q,是垂直於載台 5移動方向之方向上分開的2點。 ® 首先,在步驟1,使攝影機A、B朝X方向移動,同時 使載台5朝y方向移動,以成爲假定攝影機A、B之視野內 分別涵蓋點S、Q的位置關係,使載台5與攝影機A、B之 位置關係爲第1 8圖所示之狀態g,且以作爲第1攝影機之 攝影機A拍攝作爲第1測定對象處之點S,同時以作爲第2 攝影機之攝影機B拍攝作爲第2測定對象處之點Q。 其次,在步驟2,不移動攝影機移動機構,亦即,不 使攝影機A、B移動,僅使載台5朝y方向移動,使載台5 -30-3 Move), make the state e' and move slightly, i move the amount) plus i S, do not search, then the state, 丨 8, move to the step. That is to say, it is not necessary to search, and use the first shift of the photographing 5, the point P, the Q, and the non-existent Q direction to make a slight movement. P1, Q -29-1290613^ The captured image, the first and second images of the reference scale 13, and the first, second, and third movement amounts of the stage 5 are not stored. To calculate the coordinates of points P and Q. The coordinates of points R and S are also calculated in the same manner. In step 10, the size between each of the reference marks and the angle formed by the two straight lines connecting the lines between the reference marks are calculated from the coordinates of the respective calculated points. For example, the distance (size) between the coordinates of the reference marks P and Q to the reference marks P and Q is calculated, or the angle between the straight line connecting the reference marks P and Q and the straight line connecting the reference marks Q and S is calculated, for example. That is, the degree of orthogonality is calculated. Thus, since the angle between the reference marks P, Q, R, and S on the substrate 12 or the line connecting the marks is calculated, the deformation and the degree of orthogonality of the pattern on the substrate can be grasped. Fig. 17 is a view showing a procedure of measuring the coordinates of the reference marks S and Q of the substrate 12 by using the cameras A and B as the first and second cameras. The points S and Q at the first and second measurement targets are two points which are perpendicular to the direction in which the stage 5 moves. ® First, in step 1, the cameras A and B are moved in the X direction, and the stage 5 is moved in the y direction so that the positions of the points S and Q are assumed in the fields of view of the cameras A and B, respectively. 5, the positional relationship with the cameras A and B is the state g shown in FIG. 18, and the point S as the first measurement target is taken by the camera A as the first camera, and the camera B as the second camera is photographed. It is the point Q at the second measurement target. Next, in step 2, the camera moving mechanism is not moved, that is, without moving the cameras A and B, only the stage 5 is moved in the y direction, so that the stage 5 -30-
I2906B 與攝影機A、B之位置關係爲第19圖所示之狀態h,且以 作爲第1、第2攝影機之攝影機A、B分別拍攝基準標尺13, 以取得第1及第2圖像。在步驟3,使用利用攝影機A、B 所得之點S、Q之圖像、利用攝影機A、B所得之基準標尺 13之第1及第2圖像,以及載台5之移動量,藉由圖像處 理及運算來算出點Q、S之座標。 第20圖表示使用攝影機A〜C來測定第21圖所示之基 板1 2上之點T在基板座標系之座標的步驟,是對應於第5 φ 圖的圖。 基板1 2上之點T,例如是自配線圖案中選出的圖形中 心或圖形之轉角處等特徵點。 首先,在步驟1,移動攝影機移動機構,使攝影機A、 C朝X方向移動,同時使載台5朝y方向移動,以成爲假 定攝影機A、C之視野內分別涵蓋點S、Q之位置關係,使 載台5與攝影機A、C之位置關係爲第21圖所示之狀態i, 且以攝影機A拍攝點S,同時以攝影機C拍攝點Q。The positional relationship between the I2906B and the cameras A and B is the state h shown in Fig. 19, and the reference scales 13 are respectively captured by the cameras A and B as the first and second cameras to acquire the first and second images. In step 3, the images of the points S and Q obtained by the cameras A and B, the first and second images of the reference scale 13 obtained by the cameras A and B, and the movement amount of the stage 5 are used. The coordinates of points Q and S are calculated like processing and calculation. Fig. 20 is a view showing a step of measuring the coordinates of the point T on the substrate 12 shown in Fig. 21 on the substrate coordinate system using the cameras A to C, and corresponds to the fifth φ diagram. The point T on the substrate 12 is, for example, a feature point such as a pattern center selected from the wiring pattern or a corner of the pattern. First, in step 1, the camera moving mechanism is moved to move the cameras A and C in the X direction, and the stage 5 is moved in the y direction so that the positional relationship between the points S and Q is assumed in the fields of view of the cameras A and C. The positional relationship between the stage 5 and the cameras A and C is the state i shown in Fig. 21, and the point S is taken by the camera A, and the point Q is photographed by the camera C.
• 此外,在此步驟1,攝影機B較佳爲:與攝影機A、C 之移動同時,也事先移動至假定點T會僅因載台5之移動 而納入視野內的位置。亦即,在攝影機B之X方向上之移 動可能導致攝影機A、C之視野位置變動之情況下,例如 在攝影機B之移動所引起的振動影響攝影機A、C之視野 位置之情況下,在使攝影機A、C朝X方向移動時,同時事 先使攝影機B也朝X方向移動,藉此可以防止由攝影機A、 C進行拍攝之後,攝影機A、C之視野位置產生變動。 -31- 1290613 其次,在步驟2,使載台5朝y方向移動,進行第1 移動’使載台5與攝影機B之位置關係爲第22圖所示之狀 態j,且以攝影機B拍攝點T。 其次,在步驟3,不移動攝影機移動機構,亦即,不 移動攝影機A〜C,僅使載台5朝y方向移動,進行第2移 動’使載台5與攝影機A〜C之位置關係爲第23圖所示之 狀態k,且以攝影機A〜C分別拍攝基準標尺1 3,在步驟4, 藉由圖像處理及運算,來算出點Q、S及點T在載台座標系 φ 之座標。 其次,在步驟5,可以使用點Q、S之座標來決定相對 於載台座標系的基板座標系,然後,將在載台座標系既求 得之點T之座標轉換爲基板座標系。將點T之座標轉換爲 基板座標系的理由是:點T在設計上之座標原本以基板座 標系來表示,所以,若事先將點τ之實測座標轉換爲在基 板座標系之座標,即可將點T之實測座標與設計上之座標 直接比較,很方便。 Φ 在此,就自載台座標系轉換爲基板座標系加以說明。 若身爲基板12上2點之點Q及點S在基板座標系之 xy座標爲已知,則測定此等點Q、s在載台座標系之xy座 標,即可求取兩座標系原點彼此之位置關係(例如:基板座 標系原點在載台座標系之座標),以及兩座標系之座標軸彼 此所成的角度’故可以使用該位置關係及角度來進行兩座 標系相互之座標轉換。但是,在例如將點Q設於基板座標 系之座標原點後之情況下,即使點S在基板座標系之設計 •32- 1290613. 上之座標爲(Sx,〇),點S自點Q算起之距離實際上可能由 於製造誤差而偏離s X —點點,所以,點S之座標不算已知。 然而’定義連接點Q及點S之線爲基板座標系之X座標軸, 即可求取載台座標系之x軸與基板座標系之χ軸所成之角 度。因此,本例中,因可以獲得點Q(亦即,基板座標系之 原點)在載台座標系之座標,以及兩座標系之χ軸彼此所成 之角度’故可以使用該座標及角度來進行兩座標系相互之 座標轉換。 • 此第20圖之測定步驟可以視爲一種使用稱爲十字標 記S、Q的從基板12上之可拍攝的圖案選出之至少2個基 準標記來求取基板1 2上之圖案之位置及姿態的方法來了 解。 又,上述第20圖之測定步驟可以視爲一種求取位置如 下之方法來了解:以第1攝影機(攝影機Α)來拍攝基板12 上之第1測定對象處(點S),且以第2攝影機(攝影機C)來 拍攝第2測定對象處(點Q),不移動用以支撐第1及第2攝 • 影機的各移動機構,在此狀態,使載台5移動,以第1及 第2攝影機分別拍攝基準標尺1 3,藉由移動量測定器來測 定自第1及第2測定對象處之拍攝到基準標尺1 3之拍攝前 載台5之移動量,且使用所獲得之第1及第2測定對象處 之圖像、以第1及第2攝影機分別拍攝所得之基準標尺1 3 之第1及第2圖像,以及載台5之移動量,來求取第1及 第2測定對象處之位置。 再者,上述第20圖之測定步驟可以視爲一種求取位置 -33 - I29Q613 如下之方法來了解:以第1攝影機(攝影機A)拍攝基板12 上之第1測定對象處(點S) ’不移動用以支撐第1攝影機之 移動機構,保持於第1測定對象處之拍攝後之原狀下,使 載台5做第1移動,以第2攝影機(攝影機B)拍攝基板12 上之第2測定對象處(點T),藉由移動量測定器來測定載台 5在第1移動下之第1移動量,在不移動用以支撐第1及第 2攝影機之各移動機構之狀態下,使載台5做第2移動,以 第1及第2攝影機分別拍攝基準標尺1 3,藉由移動量測定 φ 器來測定載台5在第2移動下之第2移動量,使用所獲得 之第1及第2測定對象處之圖像、以第1及第2攝影機分 別拍攝所得之基準標尺1 3之第1及第2圖像,以及載台5 之第1及第2移動量,來求取第1及第2測定對象處之位 置。 第24圖是本發明其他實施型態之位置測定裝置與第2 圖相對應的俯視圖。 與上述第2圖所示之實施型態的不同是:除了設有第 # 2圖所示之基準標尺13 (在第24圖中爲基準標尺13 a)之外, 還另外設有一個基準標尺13b,其係隔著基板12與載台5 上之基準標尺1 3 a相對側之位置。 以基準標尺13a作爲基準的基準標尺13b之位置已事 先經過測定,若拍攝基準標尺1 3b,當時之視野位置能以基 準標尺1 3 a作爲基準來求取。因此,基準標尺1 3 b任何時 候均可用來代替基準標尺丨3 a。於是,使測定步驟與前述之 各測定步驟相同,但是,在測定對象處靠近基準標尺i3b -34- 1290613· 之情況下,視情況拍攝基準標尺1 3b來代替拍攝基準標尺 1 3 a,藉此可以減少載台5之移動量,縮短測定所需之時間。 有關其他之實施型態,也可以使用更多之攝影機被支 撐於各攝影機移動機構而構成的位置測定裝置,邊移動載 台,邊依序拍攝與攝影機個數對應之測定對象處,利用各 攝影機來對基準標尺之拍攝則在共通之載台位置進行。 又,當位置測定裝置具有複數個攝影機時,將攝影機 移動機構分配設置於架台6之兩側,亦即,隔著架台6分 φ 配設置於載台移動方向之兩側。如此一來,容易將設於架 台6互異側之攝影機移動機構彼此設計成相互間不發生移 動範圍上的干涉,故可以提高攝影機間之移動獨立性。 再者,也可以設置複數個架台,於此等架台分配設置 攝影機移動機構。如此一來,不僅容易將設於互異之架台 的攝影機移動機構彼此設計成不發生移動範圍上的干涉, 而且容易設計成即便移動設於一邊之架台的攝影機移動機 構’也不能使設於另一邊之架台的攝影機移動機構所支撐 • 的攝影機之視野發生變動,故移動攝影機移動機構及載台 的動作以及拍攝動作之順序上之自由度會提高。 但是’如上所述於架台兩側設置攝影機?還是於複數 個架台設置攝影機呢?這必須考慮以下的事情:假設此等 攝影機之視野係位於載台移動方向的不同位置,基於此假 設’於載台上設置複數個基準標尺?還是在載台移動方向 加大基準標尺?在相同之載台位置使各攝影機看見不同的 基準標尺或一個基準標尺之不同部分?還是在複數個時機 -35- 1290613. 分別拍攝基準標尺並在此期間進行載台移動?若在複數個 時機分別拍攝基準標尺並在此期間進行載台移動,則在求 取測定對象處之位置時,必須也使用其移動量。 [產業上之利用可能性] 本發明例如在基板之尺寸檢查等方面有用。 【圖式簡單說明】 第1圖係顯示本發明一實施型態之位置測定系統之槪 略構成的立體圖。 第2圖係第1圖之位置測定裝置之俯視圖。 第3圖係基準標尺之放大圖。 第4圖係顯示位置測定方法之步驟之圖。 第5圖係顯示使用攝影機A來進行點P座標測定之步 驟之圖。 第6圖係顯示第5圖狀態a之位置測定裝置之俯視圖。 第7圖係顯示第5圖狀態b之位置測定裝置之俯視圖。 第8(a)、(b)圖係拍攝圖像之槪略圖,用以說明如何利 用圖像處理及運算來算出點P之座標。 第9圖係用以說明測定對象處拍攝之搜尋步驟之圖。 第10圖係顯示利用攝影機A來進行點P、Q、R、S座 標測定之步驟之圖。 第1 1圖係顯示第1 0圖狀態C之位置測定裝置之俯視 圖。 第1 2圖係顯示第1 〇圖狀態b ’之位置測定裝置之俯視 圖。 -36- 1290613, 第1 3圖係顯示第1 0圖狀態d之位置測定裝置之俯視 圖。 第1 4圖係顯示第1 0圖狀態e之位置測定裝置之俯視 圖。 第1 5圖係顯示第1 0圖狀態f之位置測定裝置之俯視 圖。 第1 6圖係顯示第1 0圖狀態e’之位置測定裝置之俯視 圖。 φ 第17圖係顯示使用攝影機A、B來測定點Q、S座標 之步驟之圖。 第1 8圖係顯示第1 7圖狀態g之位置測定裝置之俯視 圖。 第1 9圖係顯示第1 7圖狀態h之位置測定裝置之俯視 圖。 第20圖係顯示使用攝影機A〜C來測定點T座標之步 驟之圖。 φ 第21圖係顯示第20圖狀態i之位置測定裝置之俯視 圖。 第22圖係顯示第20圖狀態j之位置測定裝置之俯視 圖。 第23圖係顯示第20圖狀態k之位置測定裝置之俯視 圖。 第24圖係與本發明其他實施型態之第2圖相對應的俯 視圖。 -37- 1290613 【主要元件符號說明】 1 位置測定裝置 2 控制裝置 5 載台 6 架台 12 基板 13 基準標尺• In addition, in this step 1, the camera B is preferably moved to the position in the field of view only by the movement of the stage 5 at the same time as the movement of the cameras A and C. In other words, when the movement of the camera B in the X direction may cause the position of the cameras A and C to change, for example, when the vibration caused by the movement of the camera B affects the visual field position of the cameras A and C, When the cameras A and C move in the X direction, the camera B is also moved in the X direction in advance, thereby preventing the positions of the fields of view of the cameras A and C from being changed after the images are taken by the cameras A and C. -31- 1290613 Next, in step 2, the stage 5 is moved in the y direction, and the first movement is made 'the positional relationship between the stage 5 and the camera B is the state j shown in Fig. 22, and the point is taken by the camera B. T. Next, in step 3, the camera moving mechanism is not moved, that is, the cameras A to C are not moved, and only the stage 5 is moved in the y direction, and the second movement is made 'the positional relationship between the stage 5 and the cameras A to C is In the state k shown in Fig. 23, the reference scale 13 is photographed by the cameras A to C, respectively, and in step 4, the points Q, S and the point T are calculated in the stage coordinate system φ by image processing and calculation. coordinate. Next, in step 5, the coordinates of the points Q and S can be used to determine the substrate coordinate system relative to the stage coordinate system, and then the coordinates at the point T obtained by the stage coordinate system are converted into the substrate coordinate system. The reason for converting the coordinates of the point T to the substrate coordinate system is that the coordinates of the point T are originally represented by the substrate coordinate system. Therefore, if the measured coordinates of the point τ are converted into the coordinates of the substrate coordinate system in advance, It is convenient to directly compare the measured coordinates of point T with the coordinates of the design. Φ Here, the conversion of the self-supporting pedestal system to the substrate coordinate system will be described. If the point Q and the point S on the substrate 12 are known as the xy coordinates of the substrate coordinate system, then the coordinates of the coordinates Q and s are measured at the xy coordinates of the stage coordinate system, and the two standard systems can be obtained. The positional relationship between the points (for example, the origin of the substrate coordinate system at the coordinates of the stage coordinate system) and the angle between the coordinate axes of the two coordinate systems. Therefore, the positional relationship and angle can be used to coordinate the coordinates of the two coordinate systems. Conversion. However, in the case where, for example, the point Q is set after the coordinate origin of the substrate coordinate system, even if the point S is on the design of the substrate coordinate system, the coordinates on the 32- 1290613. are (Sx, 〇), and the point S is from the point Q. The distance calculated may actually deviate from s X - point due to manufacturing errors, so the coordinates of point S are not known. However, the line defining the joint point Q and the point S is the X coordinate axis of the substrate coordinate system, and the angle between the x-axis of the stage coordinate system and the x-axis of the substrate coordinate system can be obtained. Therefore, in this example, since the point Q (that is, the origin of the substrate coordinate system) can be obtained at the coordinates of the stage coordinate system and the angle between the two axes of the two coordinate systems, the coordinates and angle can be used. To coordinate the coordinates of the two coordinates. • The measurement step of FIG. 20 can be regarded as a position and a posture of a pattern on the substrate 1 2 using at least two reference marks selected from photographable patterns on the substrate 12 called cross marks S and Q. The way to understand. Further, the measurement step of the above-described Fig. 20 can be regarded as a method of obtaining a position where the first measurement target (point S) on the substrate 12 is photographed by the first camera (camera Α), and the second measurement is performed. The camera (camera C) captures the second measurement target (point Q), and does not move the respective moving mechanisms for supporting the first and second camera. In this state, the stage 5 is moved to the first and The second camera photographs the reference scale 13 and measures the amount of movement of the stage 5 before the shooting from the first and second measurement targets to the reference scale 13 by the movement amount measuring device, and uses the obtained 1 and the image of the second measurement target, the first and second images of the reference scale 13 obtained by the first and second cameras, and the amount of movement of the stage 5 to obtain the first and the first 2 Determine the position of the object. Furthermore, the measurement step of the above FIG. 20 can be regarded as a method of obtaining the position -33 - I29Q613 as follows: the first camera (camera A) is used to capture the first measurement target (point S) on the substrate 12 The moving mechanism for supporting the first camera is moved, and the first stage is moved to the first measurement target, and the stage 5 is moved first, and the second camera (camera B) is used to capture the second part of the substrate 12. At the measurement target point (point T), the first movement amount of the stage 5 under the first movement is measured by the movement amount measuring device, and the movement mechanism for supporting the first and second cameras is not moved. The second movement of the stage 5 is performed, and the first scale and the second camera respectively capture the reference scale 1 3, and the second amount of movement of the stage 5 under the second movement is measured by the movement amount measuring φ device, and the obtained movement amount is obtained. The images of the first and second measurement targets, the first and second images of the reference scale 13 obtained by the first and second cameras, and the first and second movement amounts of the stage 5 are The position of the first and second measurement targets is obtained. Fig. 24 is a plan view showing a position measuring device according to another embodiment of the present invention, corresponding to Fig. 2; The difference from the embodiment shown in Fig. 2 is that in addition to the reference scale 13 shown in Fig. 2 (the reference scale 13a in Fig. 24), a reference scale is additionally provided. 13b is a position on the side opposite to the reference scale 13 a on the stage 5 via the substrate 12. The position of the reference scale 13b with the reference scale 13a as a reference has been previously measured. If the reference scale 13b is photographed, the visual field position at that time can be obtained by using the reference scale 1 3 a as a reference. Therefore, the reference scale 1 3 b can be used at any time instead of the reference scale 丨 3 a. Therefore, the measurement step is the same as each of the above-described measurement steps. However, when the measurement target is close to the reference scale i3b - 34 - 1290613 ·, the reference scale 13 b is taken as appropriate instead of the imaging reference scale 1 3 a. It is possible to reduce the amount of movement of the stage 5 and shorten the time required for the measurement. In other embodiments, a position measuring device including a plurality of cameras supported by the respective camera moving mechanisms may be used, and the measuring target corresponding to the number of cameras may be sequentially photographed while moving the stage, and each camera may be used. The shooting of the reference scale is performed at the common stage position. Further, when the position measuring device has a plurality of cameras, the camera moving mechanism is disposed on both sides of the gantry 6, that is, on both sides of the stage moving direction via the gantry 6 φ. As a result, it is easy to design the camera moving mechanisms provided on the opposite sides of the gantry 6 so as not to interfere with each other in the moving range, so that the movement independence between the cameras can be improved. Furthermore, a plurality of gantry units may be provided, and the camera moving mechanism is allocated to the gantry. In this way, it is not only easy to design the camera moving mechanisms provided on the mutually different gantry to interfere with each other in the range of movement, and it is easy to design that the camera moving mechanism of the gantry disposed on one side cannot be set in another. Since the field of view of the camera supported by the camera moving mechanism of the gantry is changed, the degree of freedom in the operation of the moving camera moving mechanism and the stage and the order of the shooting operation is improved. But as mentioned above, cameras are placed on both sides of the gantry? Or is there a camera set up on multiple platforms? This must be considered as follows: Assuming that the camera's field of view is at a different position in the direction of movement of the stage, based on this assumption, a plurality of reference scales are placed on the stage. Or do you want to increase the reference scale in the direction of the stage? Do the cameras see different reference scales or different parts of a reference scale at the same stage position? Still at multiple times -35-1290613. Shoot the reference scale separately and move the stage during this time? If the reference scale is shot at a plurality of timings and the stage is moved during this time, the amount of movement must also be used when determining the position of the measurement target. [Industrial Applicability] The present invention is useful, for example, in the size inspection of a substrate. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a schematic configuration of a position measuring system according to an embodiment of the present invention. Fig. 2 is a plan view of the position measuring device of Fig. 1. Figure 3 is an enlarged view of the reference scale. Fig. 4 is a view showing the steps of the position measuring method. Fig. 5 is a view showing a step of performing point P coordinate measurement using the camera A. Fig. 6 is a plan view showing the position measuring device of the state a of Fig. 5. Fig. 7 is a plan view showing the position measuring device of the state b of Fig. 5. Figures 8(a) and (b) are sketches of captured images to illustrate how the coordinates of point P can be calculated using image processing and calculations. Fig. 9 is a view for explaining a search step of photographing at a measurement object. Fig. 10 is a view showing the steps of measuring the coordinates of points P, Q, R, and S by the camera A. Fig. 1 is a plan view showing the position measuring device in the state C of Fig. 10. Fig. 1 is a plan view showing the position measuring device of the first drawing state b'. -36- 1290613, Fig. 13 is a plan view showing the position measuring device of the state d of Fig. 10. Fig. 14 is a plan view showing the position measuring device of the state e of Fig. 10. Fig. 15 is a plan view showing the position measuring device of the state f of Fig. 10. Fig. 16 is a plan view showing the position measuring device of the state e' of Fig. 10. Fig. 17 is a view showing the steps of measuring the coordinates of the points Q and S using the cameras A and B. Fig. 18 is a plan view showing the position measuring device of the state g of Fig. 17. Fig. 19 is a plan view showing the position measuring device of the state h of Fig. 17. Fig. 20 is a view showing a step of measuring the point T coordinates using the cameras A to C. Fig. 21 is a plan view showing the position measuring device of the state i of Fig. 20. Fig. 22 is a plan view showing the position measuring device of the state j of Fig. 20. Fig. 23 is a plan view showing the position measuring device of the state k of Fig. 20. Fig. 24 is a plan view corresponding to Fig. 2 of another embodiment of the present invention. -37- 1290613 [Description of main component symbols] 1 Position measuring device 2 Control device 5 Stage 6 Stand 12 Substrate 13 Reference scale
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