本研究中提出利用靜電紡絲PVA 交聯硒化鎘量子點作為長週期光纖光柵感測
器之感測層於濕度量測之研究。首先，在單模光纖纖殼上利用CO2 雷射寫入，製
做出直徑為101 μm、週期為620 μm 的長週期光纖光柵，再將調配出的10 w.t%聚
乙烯醇(Polyvinyl Alcohol，PVA)溶液，利用靜電紡絲技術與旋轉機構製作出紡絲
層於LPFG 上，再將紡絲完的LPFG 放置真空箱中，並與戊二醛進行交聯反應，
最後將PAA-PAAm 製作而成的水凝膠混合硒化鎘量子點 (CdSe QD)，以逐層堆疊
法塗覆於長週期光纖光柵上。最終將製作完的感測器放入濕度系統箱內，以加濕
霧化器升濕，在通氮氣降濕，進行三循環的溼度實驗。
在濕度測量範圍為20 %RH 至60 %RH 中，實驗結果顯示，隨著濕度增加，
共振波長有往長波長方向飄移，傳輸損耗也有增加的趨勢，其共振波長靈敏度達
到了0.0206 nm/%RH，且R2 可達到0.951，傳輸損耗靈敏度為-0.092 dB/%RH，且
R2 可達到0.951，顯示出長週期光纖光柵感測器具有良好的線性度以及再現性等
優點。

In this study, we propose the use of electrospun PVA crosslinked with cadmium
selenide quantum dots (CdSe QD) as the sensing layer in long-period fiber grating
(LPFG) sensors for humidity measurements. Firstly, a CO2 laser is used to inscribe the
LPFG onto the cladding of a single-mode fiber, creating gratings with a diameter of 101
μm and a period of 620 μm. Then, a 10 w.t% Polyvinyl Alcohol (PVA) solution is
prepared and applied to the LPFG using electrospinning techniques combined with a
rotational mechanism to form a fibrous layer. This fibrous layer coated LPFG is then
placed in a vacuum chamber and undergoes a crosslinking reaction with glutaraldehyde.
Finally, a hydrogel composed of PAA-PAAm and CdSe QD is prepared and meticulously
layered onto the LPFG using a layer-by-layer stacking method. The completed sensor is
placed in a humidity control box, where humidity levels are increased using a humidifying
nebulizer and decreased by introducing nitrogen gas. This cycle is repeated three times to
conduct comprehensive humidity experiments.
In the humidity measurement range of 20 %RH to 60 %RH, the experimental results
iv
show that with the increase in humidity, the resonance wavelength shifts towards the
longer wavelength, and the transmission loss also tends to increase. The sensitivity of the
resonance wavelength reached 0.0206 nm/%RH, with an R2 value of 0.951, and the
sensitivity of the transmission loss was -0.092 dB/%RH, also achieving an R2 of 0.951.
This demonstrates that the long period grating sensors exhibit excellent linearity and
reproducibility.

摘要 i
ABSTRACT iii
致謝 v
目錄 vii
圖目錄 x
表目錄 xvii
第一章 序論 1
1.1 研究動機 1
1.2 研究背景 2
1.2.1 長週期光纖光柵感測器製作之文獻回顧 2
1.2.2 水凝膠感測層光纖感測器文獻回顧 43
1.2.3 光纖感測器應用於濕度實驗文獻回顧 49
1.3 研究目的 55
第二章 基礎理論 56
2.1 光纖傳輸基本原理 56
2.2 光彈理論 64
2.3 光纖光柵基礎理論 67
2.4 長週期光纖光柵耦合模態理論分析 69
2.5 長週期光纖光柵塗覆材料折射率分析 74
2.6 長週期光纖光柵應變靈敏度分析 77
2.7 長週期光纖光柵尺寸靈敏度分析 79
第三章 研究方法與步驟 81
3.1 CO2 雷射加工長週期光纖光柵製程 81
a. 製程材料與設備 82
b.製程參數 82
c.製程步驟 82
3.2 長週期光纖光柵感測器之拉伸實驗 84
a.實驗材料與設備 84
b.實驗步驟 84
3.3 長週期光纖光柵感測器靜電紡絲構築交聯網絡製程 86
a.製程材料與設備 86
b.製程參數 87
c.實驗步驟 87
3.4 長週期光纖光柵感測器水凝膠逐層組裝製程 90
a.製程材料與設備 90
b.實驗步驟 91
3.5 長週期光纖光柵感測器濕度量測實驗架構 94
a.實驗材料與設備: 94
b.實驗步驟 94
3.6 實驗設備與化學品 96
第四章 實驗結果與討論 100
4.1 長週期光纖光柵感測器元件製作 100
4.1.1 長週期光纖光柵感測器雷射燒熔之探討 100
4.1.2 長週期光纖對於拉伸頻譜的影響 107
4.2 靜電紡絲PVA 塗覆CdSe QD 感測層LPFG 光纖感測器濕度實驗 108
4.2.1 長週期光纖感測器濕度實驗 109
4.2.2 結論 – 靜電紡絲PVA 交聯CdSe QD 長週期光纖感測器濕度實驗116
4.3 濕度光纖感測器之文獻比較 117
第五章 結論 118
5.1 靜電紡絲PVA 交聯CdSe QD 水凝膠感測層用於長週期光纖感測器之結論
118
第六章 未來展望 119
6.1 CO2 雷射D 型長週期光柵光纖感測器 119
參考文獻 120

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