在本篇論文當中，我們提出一套以結構光投射(structured light projection)為基礎之高精度三維量測系統，在量測過程中，由數位式微鏡片裝置(Digital Micro-mirrors Device, DMD)所組成之投射裝置，將Gray codes圖案投射至待測物表面，並由CCD擷取因表面高度變化所形成之扭曲影像；為了得到較佳之量測精度，我們建立一套三維數學模型，並發展出一校正程序以求得系統之校正參數，透過Gray codes編譯出DMD與CCD間具有唯一性之匹配對(correspondence pair)，由匹配對與系統之校正參數可計算出待測物之座標。另外，為了提高量測解析度，我們亦提出結合Gray codes與次像素(sub-pixel)之對應性匹配方法，加上line-shifting技術的應用，可提升四倍之解析度，由實驗結果顯示，本研究系統在12 × 9 mm2量測範圍內，可達10µm之側向解析度(lateral resolution)與3µm之垂直方向解析度(vertical resolution)。

　　除此之外，我們同時針對三維量測系統提出匹配不確定度(correspondence uncertainty)之快速評估方法，由系統之校正參數可發展出三維量測系統可量測區域之空間解析度數學模型，利用此數學模型可分析出DMD 與 CCD間之對應性匹配誤差，對於量測系統，由匹配不確定度所表示之性能指標(performance index)可以被用來評估系統之最高與最低解析度之範圍；由分析顯示，在量測範圍之上半區域有最低之匹配不確定度，此結果與系統之物理排列相吻合，在可量測範圍內，匹配不確定度的變化可達37.87%。最後，藉由對塊規(gauge block)之實際量測加以驗證本理論之可行性。

　In this research, we present a high-precision surface metrology system based on structured light projection. Gray code patterns are projected onto the object surface by a DMD projection device and a CCD camera captures the distorted pattern images. For the purpose of precision measurement, a 3-D mathematical model is proposed for the system and a calibration process is developed to obtain system parameters. The pattern is encoded with a unique ID and correspondence pairs between the CCD and DMD can be found. The surface profile can be computed by the calibrated model. In order to acquire higher measurement resolution, we propose a correspondence matching method which combines Gray codes encoding and sub-pixel edge detection. With a line-shifting procedure, the measurement resolution is elevated four times higher. Experiment results demonstrate the system has measurement area of 12 × 9 mm2, with lateral resolution about 10µm and vertical resolution about 3µm.

　Furthermore, an approach for fast evaluation of correspondence uncertainty in 3-D vision metrology systems is addressed. The mathematic model of spatial resolution measurement area of a 3-D active vision system is developed from the calibrated system parameters. Using the derived model, error of correspondence matching between DMD and CCD camera is analyzed. For each measurement result, a performance index, expressed in terms of correspondence uncertainty, is used for evaluation of the upper and lower bound of resolution. Our analysis shows that the upper part of the measurement area has the smallest correspondence uncertainty, which agrees well with the real physical arrangement. The variation of correspondence uncertainty within the measurement area is around 37.87%. Finally, based on the theoretical analysis of uncertainty bounds, an experimental measurement on gauge block was carried out to validate the method.

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