本研究的目的在於建立一套運用於PCB檢測的X射線非破壞性檢測影像演算法。X射線非破壞性檢測已成為瑕疵檢測中重要的一環，然而單獨的X射線投影影像僅紀錄了投影路徑中的資訊，並無法正確判斷內藏的瑕疵，所以必須建立一套影像重建系統重建PCB立體圖像。本研究嘗試建立線型感測器的平面式斷層掃描系統（Planar Computer Tomography，PCT）系統之影像重建方法，以近似平行光束的投影為影像成像基礎，利用代數重建法（Algebraic Reconstruction Technique，ART）從數個不同角度的投影重建出PCB截面影像。然而PCT投影角度上的限制會讓的重建影像品質大幅的降低，本研究中結合了二值夾擊的方法，利用二值夾擊輔助代數重建法進行修正，避免影像收斂於局部最佳解，以期得到更好的影像品質；同時嘗試簡化疊代演算的計算量以提高影像重建速度。最後，並討論對機台定位誤差對重建三維影像之影響。

The purpose of this study is to set up a X-ray image reconstruction algorism to inspect the defect in a Printed Circuit Board（PCB）. Nowadays X-ray Nondestructive Testing（NDT）has played an important role in defect inspection but the X-ray image contains all the information the rays passed by, therefore, it is hard to inspect the inner defect of PCB correctly. The correct inspect is rely on an image reconstruction system. This study uses the Algebraic Reconstruction Technique（ART）to reconstruct the vertical section image from the Planar Computer Tomography（PCT）system of PCB of several different project angles. The X-ray is assumed to be parallel beam. The limited angle of projection in PCT reduces the image reconstruction quality. To improve the quality of reconstructed image, a method combines the binary steering mechanism with ART to get the correct convergence and avoiding the local optimum solution of ART. Furthermore, the computational algorism to increase the reconstructed speed and discussing the influence between the image and the position error in machine are discussed.

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