隨著技術水平的進步，電子零件朝著體積縮小且功能複雜化的方向前進，昔日使用的自動化光學檢測已不敷使用，許多企業已使用X射線檢測設備，藉由X射線的穿透能力得以檢測到結構內部的、更微小的缺陷。而電腦斷層掃描系統對於設備安裝精度有極高的要求，即使微小的偏差也會對最終的影像重建品質產生影響，尤其是當待測物和其瑕疵尺寸越來越小時，幾何偏差產生的偽影就越來越不能被忽視。
過往許多研究針對幾何偏差檢測方法上提出各項相關量測方式，接著以重新校正機台的方式修正偏差，但在工程上，有時機構間的微小公差或組裝誤差等即使被量測出來也難以完全消除，因此，本研究擬探討當已檢測出系統的幾何偏差量時，如何藉由各偏差量推導出當前偏斜系統真實的幾何投影軌跡模型，用以修正演算法中所使用的投影資料，精確有效地使用這些參數來重建三維影像，改善最終重建影像品質。並在重建影像的計算過程中，使用GPU同步運算的概念，進行資料平行處理，加速整體影像重建速度。

With the advancement of technology, electronic parts are moving towards smaller sizes and more complex functions. The automated optical inspection used in the past is no longer sufficient. Many companies have used X-ray inspection equipment, which uses the penetrating ability of X-rays to Smaller defects within the structure are detected. The computerized tomography system has extremely high requirements for equipment installation accuracy. Even small deviations will have an impact on the final image reconstruction quality. Especially when the size of the object to be measured and its defects become smaller and smaller, the artifacts caused by geometric deviations will Shadows can no longer be ignored.
In the past, many studies have proposed various related measurement methods for geometric deviation detection methods, and then corrected the deviation by recalibrating the machine. However, in engineering, sometimes small tolerances between mechanisms or assembly errors are difficult to measure even if they are measured. Therefore, this study intends to explore how to derive the true geometric projection trajectory model of the current deflection system from each deviation when the geometric deviation of the system has been detected to correct the projection data used in the algorithm. , use these parameters accurately and effectively to reconstruct three-dimensional images and improve the quality of the final reconstructed image. In the calculation process of reconstructed images, the concept of GPU synchronous computing is used to perform parallel processing of data to accelerate the overall image reconstruction speed.

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