改良型同步相移干涉三維形貌量測系統與技術之研發

Development of an Improved 3-D Surface Profile System and Techniques Using Simultaneous Phase Shifting Interferometry

張瑞欽(Jui-Chin Chang)

指導教授 ： 陳亮嘉

國立臺北科技大學/機電學院/自動化科技研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00371

摘要

本研究係發展一套同步相移干涉三維形貌量測系統。傳統相移干涉術在量測上最大的限制，就是量測系統對環境干擾非常地敏感，導致量測時引入誤差造成量測不準確，或是環境干擾過甚而無法實行量測。為克服此一限制，本系統應用動態相移干涉術的概念(DPSI：Dynamic Phase-Shifting Interferometry)，係只需單次取像，即可重建物體三維表面輪廓之量測法，以大幅降低環境干擾對量測的影響。本系統以泰曼-格林干涉儀作為基本架構，光源使用He-Ne雷射搭配擴束器，分光架構為一光學平板玻璃搭配偏極分光鏡與三角稜鏡，參考光路與測物光路中配置適當之偏極片、減光片及波板作為系統光強與相位的調制，使系統同時產生俱有不同干涉相位差之干涉圖。本系統CCD單次擷取的影像之中可獲得三個光場之干涉圖，其干涉相位差分別為180°、180°與0°，三個光場相對之偏位量經由校正後，配合本論文發展之二步相移演算法，可重建待測物體表面之輪廓資訊。本研究以量測一表面平整度(surface flatness)為λ/10之平面反射鏡來評估系統量測之精度與穩定性。經由實驗結果驗證，所量測得之平面度最大誤差值約為60.5 nm (0.096λ)，符合反射鏡規格所訂定之平面誤差範圍λ/10 (63.3 nm)。

關鍵字

相移干涉術 ； 環境干擾 ； 同步相移干涉儀 ； 同步取像

並列摘要

Traditional phase-shifting interferometry is very sensitive to vibration because image acquisition in various phase shifting sequences could easily introduce measurement errors from environmental influences, such as air disturbance and system structure vibration. In this dissertation, we develop a new simultaneous phase shifting interferometer for 3-D surface profilometry only with 180∘ phase shift as well as the two-step phase shifting algorithm (actually three interferograms are used in the algorithm) for constructing the phase map. In order to evaluate the developed method, a calibrated flat mirror with a surface flatness of λ/10 was measured to test the accuracy and repeatability of the developed profilometer. The Peak-Valley error of the measurement is 60.5 nm (0.096λ). This result appears acceptable because the surface flatness of the measured mirror is approximately λ/10 (63.3 nm).

並列關鍵字

Phase-shifting interferometry ； Environmental influences ； Simultaneous phase-shifting interferometer

參考文獻

[21] 賴皇文，創新型即時同步相移干涉式三維輪廓量測儀，碩士論文，國立台北科技大學自動化科技研究所，台北，2007。

[1] J. H. Bruning, D. R. Gerriott, J. E. Gallagher, D. P. Rosenfeld, A. D. White, and D. J. Brangaccio, “Digital wavefront measuring interferometer for testing optical surfaces and lenses,” Applied Optics Vol. 13, pp.2693-2703, 1974.

[2] C. L. Koliopoulos, “Simultaneous phase shift interferometer,” Proceedings of SPIE, Vol. 1531, pp.119-127, 1991.

[3] N. R. Sivakumar, W. K. Hui, K. Venkatakrishnan, and B. K. A. Ngoi, “Large surface profile measurement with Instantaneous phase-shifting interferometry,” Optical Engineering., Vol. 42, pp.367-372, 2003.

[5] J. Millerd and N. Brock, “Methods and apparatus for splitting, imaging, and measuring wavefronts in interferometry,” U.S. Patent 6304330, 2001.