光纖感測系統具有多工量測的能力以及多項優點，例如：體積小、質量輕、靈敏度高、反應速度快，有優異的彈性設計與適應性，可以在惡劣的環境中作長期的監測。同時具有高可靠度，可以作動態即時量測以及遠端監控量測；量測系統架設簡單容易，並且可以做多參數極多點監測，而本文所研發之光纖生醫感測系統在監控氧氣濃度上即具備以上之優點。
　　因此本研究利用一簡單、低成本的技術去製作光纖式高靈敏度氧氣感測器，此技術是利用溶膠凝膠(sol-gel)過程(方法)合成出微孔性薄膜(microporous film)材料，此時platinum complex [Platinum Tetrakis (Pentrafluoropheny) Porphine (PtTFPP)]或[Platinum Octaethylporphine (PtOEP)]會被侷限在微孔性薄膜的微米孔洞中，經由UV LED (380 nm)光源的激發而放射出螢光(650nm or 645nm)。
　　本文使用兩種方式去量測氧氣濃度，首先利用量測放射螢光強度之方式，因為放射螢光之強度會隨著氧氣濃度不同而改變。另一方式為量測激發光源與放射光源之相位差方式，在不同的氧氣濃度下其偵測到的相位差會隨之變化。而其中I0/I100的比值與相位差可以作為量測感測器之靈敏度，而本文使用Platinum Tetrakis Pentrafluoropheny Porphine (PtTFPP)與Platinum　Octaethylporphine (PtOEP)作為感測材料所製作出的光學式光纖氧氣感測器，其靈敏度分別可達36.25與77.88。並且以PtTFPP作為感測材料之氧氣感測器，其反應時間分別為0.6秒(激發螢光強度由100%氮氣變化到100%氧氣之所需時間)與5秒(激發螢光強度由100%氧氣變化到100%氮氣之所需時間)，而以PtOEP作為感測材料之氧氣感測器，其反應時間分別為0.7秒(激發螢光強度由100%氮氣變化到100%氧氣之所需時間)與14秒(激發螢光強度由100%氧氣變化到100%氮氣之所需時間)。由以上之實驗結果顯示出本研究所提出的光纖式氧氣感測器具有更高的靈敏度以及更快的反應時間。

　　The past two decades have seen a rapidly growing interest in the field of fiber-optic sensors. This growth in interest has been brought into effect mainly by the advances made in the related field like opto-electronics and biological. Some of the principal reasons for the popularity of optical fiber based sensor systems are small size, light weight, immunity to electromagnetic interference (EMI), passive (all dielectric) composition, high temperature performance, large bandwidth, higher sensitivity as compared to existing techniques, and multiplexing capabilities.
　　A simple, low-cost technique for the fabrication of fiber-optic sensor for oxygen is described and preliminary results obtained using the sensor is reported. The technique is based on coating the end of an optical fiber with a microporous film prepared by the sol-gel process. A platinum complex [Platinum Tetrakis Pentrafluoropheny Porphine (PtTFPP)] or [Platinum Octaethylporphine (PtOEP)] is trapped in the porous film. In this sensor configuration the complex is exited by the 380 nm radiation and guided by the optical fiber.
　　We introduce two methods for monitoring the gas oxygen concentration : Intensity Measurement System and Phase Modulation Measurement System. The luminescence from such complex is known to be quenched by oxygen and the sensor exhibit respectable quenching behavior when exposed to various concentrations of oxygen. The ratio I0/I100 is used as a measure of the sensitivity of the sensor. I0/I100 values of PtTFPP or PtOEP immobilized in n-octyltriethoxysilane (Octyl-triEOS) / tetraethylorthosilane (TEOS) composite xerogels are estimated to be 36.25 and 77.88, respectively. The response times of PtTFPP immobilized in (Octyl-triEOS)/(TEOS) composite xerogels are 0.6 sec on going from nitrogen to oxygen and 5 sec on going from oxygen to nitrogen, respectively. In addition, the response times of PtOEP immobilized in (Octyl-triEOS)/(TEOS) composite xerogels are 0.7 sec on going from nitrogen to oxygen and 14 sec on going from oxygen to nitrogen, respectively. These results indicate that the fiber-optic oxygen sensor based on the platinum complex exhibits greater sensitivity, stability and faster response time as compared to the existing ones.

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