Fabry-Pérot光纖干涉儀具有結構微小及靈敏度高的特性，因此被廣泛研究並應用在各種不同的領域之中，它是在光纖中製造出兩道反射面來產生兩道具有光程差的反射光而形成干涉。外在環境變化會使光程差受到影響，因此我們可以透過觀察Fabry-Pérot光纖干涉儀的干涉頻譜變化來進行感測。然而，傳統製作Fabry-Pérot光纖干涉儀的過程，牽涉到化學蝕刻、飛秒雷射或熔接不同種類的光纖，使得製作過程較為複雜且昂貴。本篇論文中，我們利用聚二甲基矽氧烷(Polydimethylsiloxane, PDMS)在光纖末端形成微透鏡結構以製作光纖Fabry-Pérot干涉儀，聚合物微透鏡可與光纖及空氣形成兩道反射面，進而形成Fabry-Pérot共振腔。由於PDMS固化後具有良好彈性及可回復性，僅需利用PDMS的表面張力便能於光纖末端形成微透鏡結構，因此製作過程相當簡單、重複性高且成本低。
我們利用此PDMS微透鏡Fabry-Pérot光纖干涉儀進行溫度、折射率、位移與傾斜角度的感測。在30°C~65°C的量測範圍內，我們所製作的元件展示了良好的穩定性及線性響應，其中曲率半徑為130μm的元件其溫度靈敏度可達631pm/°C。當外在環境折射率改變時，干涉頻譜的峰值強度會產生變化，其中曲率半徑為93μm之元件在折射率1.333~1.3997範圍間的靈敏度為-59.61dB/RIU。在位移感測範圍為0~3μm時，曲率半徑103μm之元件的靈敏度可達-50.98nm/μm，表現優於其他文獻所提出之位移感測器。而在傾斜角度感測時，隨著傾斜角度增加，干涉頻譜的消光比會減少，並且在0°~5°的量測範圍內，會有部分區域呈現線性變化的趨勢。此外，利用PDMS所製作的元件於實驗前後外觀並無明顯變化，也說明了PDMS確實具有良好的回復性。

Fiber-optic Fabry-Pérot interferometers (FFPIs) have been widely utilized in many areas due to their advantages of compact size and high sensitivity. FFPIs have two reflective interfaces. As light propagates to the two interfaces, we can get two reflective light beams with different optical paths to form the interference spectrum. The optical path difference will be influenced by the surrounding environment. As a result, we can use the FFPIs for sensing applications. In previous studies, the FFPIs are fabricated by etching, femtosecond lasers or splicing different types of fibers. However, those fabrication processes are complicated or expensive. In this thesis, we fabricate a FFPI which is based on a Polydimethylsiloxane (PDMS) microlens on a fiber tip. It has simple and low-cost fabrication process. The PDMS microlens can function as the Fabry-Pérot cavity which is flexible and recoverable.
We use the PDMS-microlens-based FFPI for sensing applications of temperature, refractive index, displacement, and tilt angle. The temperature sensitivity of the FFPI with the radius of curvature R = 130μm is 631pm/°C between 30°C~65°C. When we vary the surrounding refractive index, the intensity of interference peak will be changed. The refractive index sensitivity of the FFPI with R = 93μm is -59.61dB/RIU in the refractive index range of 1.333~1.3997. The sensitivity of displacement is -50.98nm/μm for the FFPI with R = 103μm, which is better than other displacement sensors. In the tilt angle measurement, when the tilt angle is increased, the extinction ratio is decreased. We have also found that the FFPI with smaller R has a larger critical angle. In addition, the appearances of the PDMS microlens have no change after measurement, which demonstrates that the PDMS microlens has the good recoverable property.

論文審定書 i
誌謝 ii
中文摘要 iii
Abstract iv
目錄 vi
表目錄 viii
圖目錄 ix
第一章 緒論 1
1-1 光纖感測器 1
1-2 光纖干涉儀 3
1-3 研究動機 12
第二章 Fabry-Pérot光纖干涉儀原理 13
2-1 Fabry-Pérot干涉儀 13
2-2 Fabry-Pérot光纖干涉儀 21
第三章 PDMS微透鏡Fabry-Pérot光纖干涉儀 25
3-1 聚合物微透鏡Fabry-Pérot光纖干涉儀結構 25
3-2 PDMS材料特性 27
3-3 PDMS微透鏡Fabry-Pérot光纖干涉儀製作方式 29
第四章 PDMS微透鏡Fabry-Pérot光纖干涉儀基本特性 34
4-1 實驗架設 34
4-2 量測結果與討論 36
第五章 PDMS微透鏡Fabry-Pérot光纖干涉儀感測應用 41
5-1 溫度感測 41
5-2 折射率感測 46
5-3 位移感測 51
5-4 傾斜角度感測 56
第六章 結論 62
參考文獻 63

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