臺灣博碩士論文加值系統

在光學三維量測領域中，目前一般使用條紋反射法對鏡射面物體進行三維形貌量測。但鏡射面量測系統在遇上具有較大曲面的鏡射面物體時，往往會因為光資訊無法反射回感測器，而有部份區域無法量測。鏡射面量測系統無法量測大曲面鏡射物體的問題，實際上屬於斜率量測範圍的問題。本研究用座標化的量測系統模型，並對物體的斜率量測範圍進行推導，從推導的數學幾何模型參數結果中，提出較適合於量測大曲面鏡射物體的一種光學量測系統設計。
本研究亦提出一種量測方法，使用格雷碼作為條紋結構光，以兩個閾值進行條紋結構資訊編碼，運用物體邊緣陰影資訊，基於三維向量的概念，計算資訊重建初始值，並以路徑積分法重建物體整體表面高度資訊。量測實驗結果證明，本研究量測系統的量測最大三維誤差，可以控制在待測物體最大水平尺寸的0.35%以下，並且最大可量測到表面斜率分佈為 -0.5 ~ 0.5 的大曲面鏡射物體。同時，本研究的量測系統適用於量測球面和自由曲面的鏡射面樣本。

Nowadays, the fringe reflection technique is widely used to measure specular objects. However, the exiting specular surface measuring system cannot measure objects with highly curved surface. Because the highly curved surface means that the surface slope distribution range is too large to be measured. In this research, a coordinate system model is used to describe all the parameters in the system and provide a model of optical system design having large slope measurable range from derived model.
This research also provides a measuring method which uses Gray Code as structured light and uses two thresholds for encoding structured light information to calculate the initial height value using shadow information next to object’s edge based on three-dimensional vector concept. Then, use the path integration method to reconstruct the whole object surface. It is proved, the maximum error of the proposed system can be controlled under 0.35% of the lateral size of measured samples and the slope measurable range of the proposed system is -0.5 ~ 0.5. At the same time, the proposed system is suitable for measuring spherical and free-form specular objects.

誌謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VI
表目錄 IX
符號表 X
1 緒論 1
1.1 研究背景 1
1.2 研究動機 3
1.3 研究目的 3
2 文獻回顧 4
2.1 引言 4
2.2 鏡面量測方法 5
2.2.1 條紋反射法文獻 5
2.2.2 掃描射線法文獻 6
2.2.3 鏡面量測方法比較 6
2.3 條紋結構光 7
2.3.1 二進位碼介紹 8
2.3.2 二進位碼文獻 9
2.3.3 格雷碼介紹 9
2.3.4 格雷碼文獻 10
2.3.5 條紋結構光比較 12
2.4 資訊重建初始值問題 13
2.4.1 資訊重建初始值問題介紹 13
2.4.2 資訊重建初始值問題文獻 14
2.4.3 資訊重建初始值問題比較 16
2.5 曲面鏡射物體量測 17
2.5.1 曲面鏡射物體量測介紹 17
2.5.2 曲面鏡射物體量測文獻 18
2.5.3 曲面鏡射物體量測系統比較 21
2.6 文獻分析與總結 22
3 研究方法 23
3.1 鏡面量測系統光學模型 23
3.1.1 條紋反射法 23
3.1.2 系統幾何光學模型 24
3.1.3 系統斜率量測範圍分析 28
3.1.4 系統斜率量測解析度極限分析 31
3.2 系統校正 32
3.3 高度初始值問題 44
3.3.1 陰影向量測高法 44
3.3.2 高度初始值問題方法比較 47
3.4 數位結構光 49
3.4.1 格雷碼 49
3.4.2 雙閾值法 50
3.5 物體表面資訊重建演算法 54
3.5.1 路徑積分法 54
3.5.2 物體表面資訊重建流程 55
3.6 三維點雲驗證 59
3.6.1 最小環帶球 59
3.6.2 迭代最近點法 60
4 量測系統架構與實驗流程 61
4.1 系統光學架構 61
4.2 系統硬體規格 63
4.2.1 光源部分 63
4.2.2 影像擷取部分 64
4.3 系統軟體架構 67
4.4 實驗步驟與流程 69
5 量測結果與討論 73
5.1 量測結果 73
5.1.1 焦長12.5 mm凸面鏡之量測 73
5.1.2 焦長25 mm凸面鏡之量測 75
5.1.3 自由曲面樣本1之量測 77
5.1.4 自由曲面樣本2之量測 79
5.2 量測精度驗證 81
5.2.1 焦長12.5 mm凸面鏡之精度驗證 81
5.2.2 焦長25 mm凸面鏡之精度驗證 82
5.2.3 自由曲面樣本1之精度驗證 82
5.2.4 自由曲面樣本2之精度驗證 83
5.3 陰影向量測高法量測結果 84
5.4 雙閾值法結果比較 85
5.5 誤差分析 88
5.6 討論 92
6 結論與未來展望 95
6.1 結論 95
6.2 未來展望 97
參考文獻 98

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