光柵式結構光源三維掃描儀的建立涵蓋了立體光學理論、相機校正理論、結構光編碼理論、對位座標理論及整合所有軟硬體所需程式撰寫技巧，是一項充滿挑戰的儀器。本研究目的在於開發一掃描範圍為一般牙模掃描儀兩倍大小之光柵式結構光源三維掃描儀，並在此過程中揭露完成此裝置所需用到的各種理論與實際應用時發生的問題與克服的方法。
本研究以雙相機的立體視覺系統做為開端，並以蔡氏校正取得兩台相機的內、外參數，校正的過程包針孔相機模型的參數推導與極線幾何方法的運用。取得相機的校正檔後，結合投影機投射光柵式結構光格雷碼影像與相位移影像，將掃描範圍由一點擴增至投影機投射範圍，並且投射兩張影像篩選出不適合做為編碼點的座標值。此外，為取得完整受測物雲點，本研究使用TrICP演算法對多次掃描產生之雲點進行座標對位，並且為了加速對位的過程發展出對位雲點校正塊，儲存各掃描角度對位時所需的轉換矩陣。最後，透過校正板、平板、鉻鋼珠與對位雲點校正塊的測試，本研究的校正精度為0.026±0.02mm、單次掃描精度0.158±0.033mm、多次掃描精度0.225±0.150mm的結果。

Three-dimensional raster scanner is a challenging instrument. To complete this machine needs many theories, such as stereovision, camera calibration, structured light techniques, positioning registration and skill of software development. Purpose of this study is to develop a three-dimensional raster scanner, which has double scanning range compared to normal dental scanner. This study employs stereo visualization theory with dual cameras, in order to obtain two camera's parameters by Tsai's calibration method. After camera calibration, we use a projector to provide the light source with a computer generated structure gray image. According to the position of the projector, range of scanning domain were amplified. And then, we increase the number of projection image to avoid deviation points. In order to gain entire cloud points for further analysis, we used TrICP algorithm to register the coordinate of point cloud from several scan positions. We also use a calibrated block to accelerate the speed of registration processes by saving each transition matrix for every positions. Finally, tests of a few simple cases reveal that the calibration accuracy is 0.026 ± 0.02mm, the single-scan accuracy is 0.158 ± 0.033mm, and the multiple scans accuracy is 0.225 ± 0.150mm.

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