以雙波長菲佐干涉術進行距離及角度同步量測法之研發

Development of a simultaneous distance and angle measuring method using two-wavelength Fizeau interferometry

尤澤龍(Tse-Lung Yu)

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(2016年)

https://doi.org/10.6342/NTU201602063

摘要

本研究研發一套運用雙波長菲佐干涉術之距離及角度同步量測系統，本研究之技術發展成功整合雙波長干涉術、雙折射晶體之分光效應、相移術及角度量測等原理達成同時量測距離與角度之目標。此量測系統包含光纖及探頭兩部分，由偏極態保持光纖 (PM fiber)、偏振片耦合器、高密度波長分波多工器、光循環器、偏極態分光器和光偵測器等元件作為光纖系統組成元件；準直鏡、Savart 稜鏡、分光鏡和壓電位移平台作為探頭系統組成元件，光源部分利用紅外光頻譜找出兩個相近的波段，進行雙波長干涉並減少相位模糊問題，並使用Savart稜鏡作為雙折射晶體進行分光以量測角度，再加上精密奈米級壓電位移平台進行相移術，最後以光纖作為訊號傳遞元件所形成的二對P與S偏極態形成光干涉訊號後，用光偵測器及電腦進行訊號處理同時得到距離及角度資訊。
經過多次實驗證明後，本系統於良好環境控制下進行單波長位移距離量測時可得到0.43 %的誤差；進行雙波長位移距離量測時，可得到1.0 %的誤差；進行傾斜角度量測時，可得到小於全量測範圍之3.55 %的誤差。此系統除前述優點外，亦具備開發成為小型化探頭的潛力，未來亦可應用此量測系統於工具機之三軸位移量測。

關鍵字

雙波長干涉 ； 距離量測 ； 角度量測 ； 光纖量測 ； 菲佐干涉術

並列摘要

The research is aimed to develop a simultaneous distance and tilting angle measuring method by using two-wavelength Fizeau interference with a birefringent crystal (Savart prism) as a beam splitter. In addition, this system features of small size, easy-to-build and high feasibility. Besides, the fiber part in the system is established by using a polarization-maintaining optical fiber (PMF or PM fiber), polarizer, dense wavelength division multiplexing (DWDM), circulator and polarized beam splitter (PBS). Probe part in this system is built by using a collimator, a Savart prism, a beam splitter and a piezoelectric transducer (PZT).
The developed measuring method employs Fizeau-based two-wavelength interference, light splitting by birefringent crystal and multi-step phase shifting to achieve the simultaneous measurement of positioning distance and tilting angle. Also, two specific wavelengths, which are close to each other, are used to form two wavelength interference with reduced phase ambiguity. A Savart plate is used to make two parallel beams so that tilting angle of an object can be measured. A multi-step phase-shifting principle by modulating the beam splitter with a PZT is used determine phase information from two pairs of p- and s-polarization interference beams, so the distance and tilting angle signal can be detected and processed by using photon detectors and personal computer, respectively.
As proved by experiments, the developed measuring method can detect a distance with 0.43 % uncertainty of the overall measuring range under environmental-controlled conditions by using single wavelength; 1.00 % uncertainty of the total measuring range by using two wavelength, respectively. Meanwhile, the tilting angle of the stage can be measured with error less than 3.55% of the total measuring angle range.

並列關鍵字

Two-wavelength interference ； distance measurement ； angle measurement ； fiber-based measuring system ； Fizeau interferometry

參考文獻

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