Mach-Zehnder 光纖干涉儀擁有許多優點，如體積小、解析度高以及感測靈敏
度高等，因此有許多的研究結果被廣泛地提出，其中開放式共振腔的 Mach
Zehnder 光纖干涉儀更因為擁有極高的折射率感測特性，因此適合應用於感測微
小的折射率變化。過去曾有研究團隊利用錯位熔接的方式來製作開放式元件，但
是製程步驟困難，且需要精準地對齊熔接；亦有團隊提出以飛秒雷射進行加工，
但製程上需要昂貴實驗儀器而使製程成本大幅提高。本論文將利用光纖研磨的技
術製作斜角光纖，並熔接蝕刻後的光子晶體光纖，製作成開放式 Mach-Zehnder
光纖干涉儀。相較於錯位熔接製程，我們所提出的製程步驟較簡單，且不需要使
用飛秒雷射製程，可以有效地降低製程成本。
我們將所製作的開放式 Mach-Zehnder 光纖干涉儀進行實驗量測，並討論不
同纖芯直徑以及共振腔長度對干涉條紋的影響，且由自由頻譜範圍增加的現象可
以證明液體能成功地填入共振腔中。在感測結果方面，我們所製作的元件在折射
率範圍為 1.3330 至 1.3418 以及氣壓範圍為 0 至 20 psi 時，皆擁有極高的感測靈
敏度，分別為-10462.7 nm/RIU 和-63.71 pm/psi，並可以計算出其感測極限為
-64.78 10  RIU 以及 0.159 psi，說明元件可以感測微小的折射率變化。此外，此元
件的溫度靈敏度為31.23 pm/℃，而應變靈敏度則為1.06 pm/με和 -4 1.04 10  dB/με。
上述之感測特性皆展示了我們所製作的開放式 Mach-Zehnder 光纖干涉儀擁有極
高的潛力應用於環境感測上。

Fiber-optic Mach-Zehnder interferometers (MZIs) have been widely proposed due
to their advantages such as compact size, high resolution, and high sensing sensitivity.
Especially, MZIs with open cavities exhibit ultrahigh refractive index (RI) sensitivities,
which can be applied in detecting slight RI variation. Previous studies have proposed
several open-cavity MZIs by splicing fibres with a large lateral offset, which are
difficult to be fabricated due to the required precise alignment. Some research groups
utilize femtosecond (fs) lasers to fabricate open-cavity MZIs, which results in high cost.
In this thesis we propose a method to fabricate an open-cavity MZI by splicing an
etched photonic crystal fiber (PCF) with a beveled fiber formed by fiber polishing
technology. Our manufacturing process is simple, and no high-cost fs lasers are required.
The interference properties of our MZI are experimentally demonstrated and
discussed with different core sizes and cavity lengthes. It is proved by the increase of
the free spectrum range that the liquid indeed can be filled into the open cavity
successfully. In sensing properties, our MZI exhibits an ultrahigh RI sensitivity of
10462.7 nm/RIU in the RI range of 1.3330 to 1.3418 and pressure sensitivity of -63.71
pm/psi in the pressure range of 0 to 20 psi. Besides, the corresponding detection limits
are -6 4.78 10  RIU and 0.159 psi, respectively, which indicates that our MZI can detect
slight RI variation. Moreover, the temperature sensitivity of our MZI is 31.23 pm/℃,
and the strain sensitivity of the MZI is 1.06 pm/με and -4 1.04 10  dB/με. As a result,
our fabricated MZI sensor possess good potential in environmental parameter sensing.

論文審定書 i
致 謝 ii
摘 要 iii
Abstract iv
目 錄 v
圖目錄 vii
表目錄 xi
第一章　　緒論 1
　　1-1　　光纖感測器 1
　　1-2　　光纖干涉儀感測器 3
　　　　1-2.1　法布立-培若光纖干涉儀(Fabry-Pérot fiber interferometer) 5
　　　　1-2.2　馬赫-桑德光纖干涉儀(Mach-Zehnder fiber interferometer) 9
　　　　1-2.3　麥克森光纖干涉儀(Michelson fiber interferometer) 12
　　　　1-2.4　薩格奈克光纖干涉儀(Sagnac fiber interferometer) 15
　　1-3　　研究動機 18
第二章　　Mach-Zehnder光纖干涉儀 19
　　2-1　　Mach-Zehnder光纖干涉儀 19
　　2-2　　開放式Mach-Zehnder光纖干涉儀 20
　　2-3　　開放式Mach-Zehnder光纖干涉儀的原理 24
第三章　　開放式Mach-Zehnder光纖干涉儀之元件製程 28
　　3-1　　元件設計 28
　　3-2　　光纖材料 29
　　3-3　　製程步驟 30
　　　　3-3.1　光纖熔接 30
　　　　3-3.2　製作同軸結構光纖 31
　　　　3-3.3　製作斜角光纖 34
　　　　3-3.4　製作開放式Mach-Zehnder光纖干涉儀 36
　　3-4　　蝕刻製程特性 37
第四章　　開放式Mach-Zehnder光纖干涉儀的干涉特性 40
　　4-1　　頻譜量測架設 40
　　4-2　　不同纖芯直徑的干涉特性量測 42
　　4-3　　不同共振腔長度的干涉特性量測 45
　　4-4　　不同研磨量之斜角光纖所形成的開放式共振腔 48
第五章　　開放式Mach-Zehnder光纖干涉儀的感測應用 51
　　5-1　　折射率感測 51
　　5-2　　氣壓感測 55
　　5-3　　溫度感測 58
　　5-4　　應變感測 61
第六章　　結論 63
參考文獻 64

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