相位移技術為三維精密測量技術中非接觸式量測的技術之一，利用投射條紋影像至物體表面來量測三維表面3D資料。近年因3D列印產業的興盛，相位移技術也被廣泛運用於三維物體的重建。由於原始的三步相位移其重建結果之相位誤差較大，而衍伸出了多步相位移演算法，利用投影三張以上的條紋影像來降低相位誤差。因此，本論文針對位移步數進行探討，期望找出以最少相位移步數，即最少的投影條紋張數，其重建結果可與投影多張條紋影像之結果相同。並探討相位移技術應用於彩色模型掃描時，所適用的顏色範圍。
由實驗結果得知，在五步相位移之後的相位誤差修正前後並無明顯差別，且在相位誤差修正前，五步相位移的平均誤差已趨近於十二步相位移的平均誤差。因此，使用五步相位移即可得到較好的重建結果。此外。物體表面傾斜方向對相位計算結果影響不大；而若要對彩色模型進行掃描，則建議模型顏色的明度（L*）宜介於51 ~ 98。

Phase-shifting technology is one of non-contact measurement methods in 3D precision measurement technology, which projects fringe images on the object surface to measure the 3D surface. In last few decades, the 3D printing industry is getting popular and, phase-shift technology is therefore widely used in 3D reconstruction. Due to three-step phase-shifting method is likely inaccurate in 3D reconstruction, several multi-step phase-shifting algorithms have been proposed. In this thesis, the author would like to determine the minimum steps, as well as minimum projected images, in phase-shifting method. We expect that the accuracy of 3D reconstruction can be as good as those by multi-step phase-shifting methods. Finally, we further discuss the effects of color in the phase-shifting algorithm.
The experiment result shows the phase error in the five-step phase-shifting method is similar to that in twelve-step, as well as higher, phase-shifting methods. As a result, five-step phase-shifting method without additional correction is recommended. The surface direction of a scanned surface does not affect the phase estimation. For scanning a color 3D object, we recommend that the lightness of the object should be between 51 and 98.

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