光斑與結構光複合式三維形貌量測研究

Research on 3-D Surface Measurement using Synthesis of Speckle and Structured Fringe Composite Patterns

謝仲安(Chung-An Hsieh)

指導教授 ： 陳亮嘉

國立臺灣大學/工學院/機械工程學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.10864

摘要

三維形貌量測在自動光學檢測上有著不可取代的地位，而三角量測法則在是最常被使用的量測方法，不管是相移術或是灰階編碼法都是利用三角量測法之原理進行量測，以往在相移術有著相位模糊的問題，故相移術所能量測的物件有所限制，當相位模糊產生時，量測的結果有極大的誤差產生；而利用雷射光斑的數位影像辨識法在量測時會有解析度較差、量測結果的邊界容易產生錯誤的問題存在；而量測解析度與量測範圍的提升一直都是相當重要的課題，為了提升量測範圍與解析度，本研究利用一個新的量測方法，結合雷射光斑與條紋結構光投影與待測物之上，利用數位影像辨識法使用雷射光斑計算絕對相位而條紋結構光利用相移術計算相對相位，藉由此方法可以將絕對與相對相位進行結合，利用此方法可以有數位影像辨識的大範圍而有較高的解析度與精度，藉由實驗驗證，此方法可達到深度解析10μm且量測範圍達到100mm，是以往相移術較難達成的量測能力。

關鍵字

自動光學檢測 ； 三維形貌量測 ； 相移術 ； 相位模糊 ； 階高限制 ； 複合圖案

並列摘要

Three-dimensional profilometry is an indispensable surface profile measuring technology for ensuring the quality of manufacturing process in the modern manufacturing industry, especially for automated optical inspection (AOI). Triangulation-based three-dimensional profilometry most frequently employed nowadays includes phase-shifting, gray-code and speckle-projecting profilometry. Theoretically, the measuring depth is traded off with the measuring resolution as a physical limit for 3-D optical detection. To address this measuring barrier, this article presents a new optical measuring method for one-shot three-dimensional profilometry, in which random speckles and structured fringes are simultaneously projected onto tested objects for forming a pair of deformed speckle and fringe images to be acquired concurrently. The speckle image is utilized to determine an absolute phase of each position using digital image correlation (DIC) while the fringe image is employed to determine a relative phase by using phase shifting profilometry (PSP). Each pair of absolute and relative phases corresponding to each measured position is respectively converted into an absolute and a relative depth. As a result, depth information of each position on the surface of the object is then reconstructed by synthesizing the corresponding absolute depth and the relative depth. With this, full-field surface profilometry with high measuring accuracy and large range of surface depth can be realized. Verified by some measuring experiments, the developed method can achieve a measuring depth resolution of 10

並列關鍵字

Automated optical inspection (AOI) ； three-dimensional profilometry ； digital image correlation (DIC) ； Phase shifting profilometry

參考文獻

[1] G. Sansoni, M. Carocci, and R. Rodella, "Three-dimensional vision based on a combination of gray-code and phase-shift light projection: analysis and compensation of the systematic errors," APPLIED OPTICS, vol. 38, pp. 6565-6573, 1999.

[2] S. Zhang and P. Huang, "High-resolution, Real-time 3D Shape Acquisition," Computer Society Conference on Computer Vision and Pattern Recognition Workshops, vol. 3, pp. 28-37, 2004.

[3] S. Zhang and S. T. Yau, "High-resolution, real-time 3D absolute coordinate measurement based on a phase-shifting method," Opt Express, vol. 14, pp. 2644-9, Apr 3 2006.

[4] P. S. Huang, "Color phase-shifting technique for three-dimensional shape measurement," Optical Engineering, vol. 45, p. 013602, 2006.

[5] J. Huo, Q. Wu, and X. Zeng, "A technique of phase-shifting for 3-D measurement using spectral-transform," Optics and Lasers in Engineering, vol. 51, pp. 1133-1137, 2013.