A time synchronization calibration method and system for image taking and coordinate reading and a delay time calculation method thereof are disclosed. The time synchronization calibration method is as follows. Firstly, every time point, a calibrator coordinate, an operation target coordinate and an image thereof are obtained. The image similarity index of every image and the image of previous time point thereof is calculated. When the image similarity index is lower than a preset similarity index, a reading time of the image is output followed with calculating the difference of the reading time and a time delay to obtain a taking time of the image. Finally, calculating the coordinate transformation of the calibrator coordinate and the operation target coordinate, and corresponding it to the image to output an image-coordinate correspondence relation. The time delay can be obtained correctly with only one test, and provided for the consequent synchronization calibration.本發明係為一種影像拍攝與座標擷取時間同步之校正方法與校正系統及其延遲時間計算方法,其中校正方法如下:先取得每一時間點及其校正器座標、手術目標座標以及影像,接著計算每一影像與其前一時間點之影像之影像相似度,當相似度低於預設相似度時則輸出影像之讀取時間,並接著將讀取時間減掉延遲時間以得到影像之拍攝時間,最後計算拍攝時間之校正器座標及手術目標座標的座標轉換關係,並將其對應到影像以得到影像-座標轉換關係。本發明可以於一次測試中得到準確的延遲時間,並使用此延遲時間進行所有後續之手術導引校正。S100‧‧‧影像拍攝與座標擷取時間同步之校正方法S10‧‧‧取得每一時間點之一校正器座標及一手術目標座標S20‧‧‧讀取每一時間點之一影像S30‧‧‧計算影像相似度S40‧‧‧輸出一讀取時間S50‧‧‧計算一拍攝時間S60‧‧‧輸出一影像-座標轉換關係
