本研究著重於用非接觸主動式三維掃描，首先使用平面校正棋盤對真實攝影機進行校正，再使用雙攝影機對物體分別拍攝照片抓取相同之特徵點，其特徵點利用點狀雷射輔助標記;因拍攝位置不同對於同一特徵點在影像平面中之水平方向座標產生了水平視差 (Disparity)，利用其差距可以進一步使用水平雙攝影機模型，計算特徵點相對於左攝影機之三維座標點。利用虛擬攝影機之視埠矩陣 (Viewport matrix) 與投影矩陣 (Projection matrix) 相乘等同於真實攝影機之內參數，即可使用虛擬攝影機模擬拍攝虛擬物體模型輔助系統發展、雙攝影機模型驗證。測試實例含重建LEGO十字栓與自動鉛筆0.5mm筆芯，並使用GOM Inspect進行分析。

關鍵字: 立體視覺、水平雙攝影機模型、非接觸三維掃描、虛擬環境輔助、攝影機校正

SUMMARY
The purpose of this research is to develop noncontact 3D scanner. In order to get camera parameters, we use planar calibration pattern as marker, then use Chang’s method to get camera parameters in Matlab. We take two pictures of the object which is marked by laser point by binocular cameras individually. Because of disparity which is horizontal coordinate difference from binocular cameras, we can use disparity to calculate object’s 3D coordinate which origin is set on left camera. Hence, 3D coordinate are built in binocular camera model. However, it is hard to prove binocular camera model in reality, because there are too many uncertainties which need to handle with. If we use virtual environment, there will be no uncertainty in it. Especially, we can times Viewport matrix and Projection matrix together which are the same with camera intrinsic parameters. According to above mentioned, we can use virtual environment to verify binocular camera model. The result is quite perfect that the distance between object and camera can be calculated precisely. The scanning test contains LEGO pin and 0.5mm pencil lead, and analysis process use GOM Inspect software.

Key words : Stereo Vision, Binocular camera, noncontact 3D scanning, Virtual environment assisted, Camera calibration

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