臺灣博碩士論文加值系統

本文建構出一個由布拉格光纖光柵設計之感測器以及光纖式馬赫—詹德干涉儀組成的光學量測系統，光纖式干涉儀包含ASE寬頻光源、兩個2×2方向耦合器和光檢測器，主要是利用布拉格光纖光柵之中心波長會隨著溫度或是應變的改變，甚至是因外力改變折射率而飄移，振動訊號由波長調變經光纖式干涉儀轉換為相位干涉的方式進行量測，解調訊號方式有兩種，方法一是使用壓電陶瓷PZT進行高頻調變；方法二是使用3×3方向耦合器進行訊號解調，兩種方法皆使用MATLAB進行運算解調出振動訊號。實驗結果顯示，所架構之光學量測系統可準確地量測振動，並經由壓電式加速規，分析其頻率響應與可量測之動態範圍。

A fiber-optic measurement system which includes a FBG sensor and a Mach-Zehnder interferometer is developed to be a frequency analyzer used in vibration measurement. The Mach-Zehnder interferometer which includes one ASE light source, two fiber couplers and two photo detectors is fabricated to measure the phase difference introduced by an FBG sensor used as an accelerometer. To avoid signal fading, two methods are utilized in demodulating the vibration signals. The first uses a PZT to produce a high–frequency modulation signal in the optical system. The second is to replace the second coupler of the interferometer with a 3×3 directional coupler. Experimental results show that the fiber-optic interferometer can acquire the vibration signal from the FBG sensor and then interpret it correctly via the signal processing unit developed using MATLAB. By measuring the same vibration signal, the performance of the FBG sensor is determined as compared to a traditional accelerometer.

表目錄 Ⅲ
圖目錄 Ⅳ
第一章 緒論 1
1-1 研究動機 1
1-2 研究目的 2
1-3 文獻回顧 3
1-3-1 光纖種類與傳輸概念 3
1-3-2 光纖光柵簡述 4
1-3-3 光纖干涉儀簡述 6
1-3-4 各式光纖光柵感測器 7
1-3-5 文獻回顧總結 13
1-4 研究方法 14
第二章 光纖感測系統與其原理 15
2-1 感測原理 15
2-1-1 布拉格光纖光柵 15
2-1-2 感測器分類 17
2-1-3 光學儀器原理 19
2-2 各式干涉儀比較 21
2-3 不平衡式馬赫-詹德干涉儀 24
2-3-1 干涉儀原理 24
2-3-2 同調長度(Coherence Length) 25
2-3-3 干涉儀架構與特性分析 26
第三章 訊號處理 31
3-1 訊號調變與解調 31
3-2 主動式零差解調(Active Homodyne) 32
3-3 被動式零差解調(Passive Homodyne) 33
3-3-1 PGC解調 35
3-3-2 PZT驅動與相位關係 38
3-3-3 PZT驅動測試 39
3-3-4 3×3方向耦合器解調 42
第四章 光纖干涉系統製作與振動量測 43
4-1 實驗目的 43
4-2 實驗簡介與架構 43
4-2-1 實驗設備與架構 43
4-2-2 光行徑路線流程 47
4-2-3 PGC解調模擬 50
4-2-4 3×3耦合器解調模擬 51
4-2-5 實驗儀器校正 52
4-3 實驗流程與量測結果 53
4-3-1 訊號失真情形 54
4-3-2 PGC解調實驗結果 55
4-3-3 3×3耦合器解調實驗結果 61
4-3-4 合討論 66
第五章 光纖光柵加速度感測器設計 69
5-1 實驗簡介及感測器架構 69
5-2 實驗流程與量測結果 72
5-3 結果討論 78
第六章 結論與未來展望 79
6-1 結論 79
6-2 未來展望 80
參考文獻 81
附錄一 實驗器材 85
附錄二 光檢器(Photodetector) 88
附錄三 PZT規格 89

[1] 陳家祥, “光纖光柵量測系統與動態感測器之設計,” 國立中正大學機械工程研究所碩士論文(鄭志鈞) , 2006.
[2] K. O. Hill, B. Malo, F. Bilodeau, D. C. Johnson and J. Albert, “Bragg Gratings fabricated in monomode photosensitive optical fiber by UV exposure thorough a phase mask,” Appl. Phys. Lett., Vol. 62, pp. 1035-1037, 1993.
[3] T. Edgron, “Fiber Grating Spectra,” J. Lightwave Technol., Vol. 15, No. 8, pp. 1277-1294, 1997.
[4] B. O. Guan, H. Y. Tam, S. L. Ho, W. H. Chung and X. Y. Dong, “Simultaneous strain and temperature measurement using a single fibre Bragg grating,” Electronics Lett., Vol. 36, No. 12, pp. 1018-1019, 2000.
[5] Ph. M. Nellen, P. Mauron, A. Frank, U. Sennhauser, K. Bohnert, P. Pequignot, P. Bodor and H. Brndle, “Reliability of fiber Bragg grating based sensors for downhole applications,” Sensors and Actuators A: Physical, Vol. 103, pp 364-376, 2003.
[6] Y. Zhao, Y. Zhao and M. Zhao, “Novel force sensor based on a couple of fiber Bragg gratings,” Measurement, Vol. 38, pp 30-33, 2005.
[7] M. D. Todd, G. A. Johnson, B. A. Althouse and S. T. Vohra, “Flexural Beam-Based Fiber Bragg Grating Accelerometers,” IEEE Photon. Technol. Lett., Vol. 10, No. 11, 1998.
[8] A. Cusano, A. Cutolo, J. Nasser, M. Giordano and A. Calabro, “Dynamic strain measurements by fiber Bragg grating sensor,” Sensors and Actuators A: Physical, Vol. 110, pp 276-281, 2004.
[9] H. Y. Ling, K. T. Lau, L. Cheng and W. Jin, “Viability of using an embedded FBG sensor in a composite structure for dynamic strain measurement,” Measurement, Vol. 39, pp 328-334, 2006.
[10] N. Hirayama and Y. Sano, “Fiber Bragg grating temperature sensor for practical use,” ISA Transactions, Vol. 39, pp 169-173, 2000.
[11] J. Cong, X. Zhang, K. Chen and J. Xu, “Fiber optic Bragg grating sensor based on hydrogels for measuring salinity,” Sensors and Actuators B: Chemical, Vol. 87, pp. 487-490, 2002.
[12] J. R. Lee and H. Tsuba, “A novel fiber Bragg grating acoustic emission sensor head for mechanical tests,” Scripta Materialia, Vol. 53, pp. 1181-1186, 2005.
[13] A. Othonos and K. Kalli, “Fiber Bragg Gratings: Fundamentals and Applications in Telecommunications and Sensing,” Artech House, 1999.
[14] G. Meltz and W. W. Morey, “Bragg grating formation and germanosilicate fiber photosensitivity,” in Proc. SPIE, Vol. 1516, pp. 185-199, 1991.
[15] A. D. Kersey, M. A. Davis, H. J. Patrick M. LeBlanc, K. P. Koo, C. G. Askins, M. A. Putnam and E. J. Friebele, “Fiber Grating sensors,” Lightwave Technology, Vol. 15, No. 8, pp. 1442-1463, 1997.
[16] P. Fomitchov and S. Krishnaswamy, “Response of a fiber Bragg grating ultrasonic sensor,” Opt. Eng., Vol. 42, No.4, pp. 956-963, 2003.
[17] J. T. Verdeyen, “LASER ELECTRONICS,” THIRD EDITION, Prentice Hall, Ch. 10, 1998.
[18] A. Ghatak and K. Thyagarajan, “Introduction to fiber optics,” Cambridge University Press, Ch. 17, 1998.
[19] E. Udd, “Fiber optic sensors,” John Wiley and Sons, Inc., 1991.
[20] M. S. Tsai, “Electronic Modulation of Laser Vibrometers to Remove the Effect of Background Illumination,” Pennsylvania State University, 1994.
[21] E. Hecht, ”OPTICS”, Addison Wesley, FOURTH EDITION, 2001.
[22] 黃國挺, “雙桑克干涉式光纖水中聽音器之設計與解調,”國立中山大學電機工程研究所碩士論文(陳茂雄、林武文), 2004.
[23] D. A. Jackson, R. Priest, A. Dandridge and A. B. Tveten, “Elimination of drift in a single-mode optical fiber interferometer using a piezoelectrically stretched coiled fiber,” Appl. Opt., Vol. 19, No. 17, pp. 2926-2929, 1980.
[24] A. Dandridge, A. B. Tveten and T. G. Giallorenzi, “Homodyne Demodulation Scheme for Fiber Optic Sensors Using Phase Generated Carrier,” IEEE J. Quantum Electron, Vol. QE-18, No. 10, pp.1647-1652, 1982.
[25] S. K. Sheem, T. G. Giallorenzi and K. P. Koo, “Optical techniques to solve the signal fading problem in fiber interferometers,” Appl. Opt., Vol. 21, No. 4, pp. 689-693, 1982.
[26] 郭士傑, “自動化光纖光柵感測器的研究,” 國立台灣科技大學電子工程研究所碩士論文(張嘉男), 2002.
[27] K. P. Koo, A. B. Tveten and A. Dandridge, “Passive stabilization scheme for fiber interferometers using (3×3) fiber directional couplers,” Appl. Phys. Lett., Vol. 41, No. 7, pp. 616-618, 1982.
[28] B&K, “An Introduction to Vibration Measurement,” B&K, 1982.
[29] A. Mita, and I. Yokoi, “Fiber Bragg grating accelerometer for buildings and civil infrastructures,” in Proc. SPIE, Vol. 4330, pp. 479-486, 2001.
[30] M. LeBlanc, S. T. Vohra, T. E. Tsai, and E. J. Friebele, “Transverse load sensing by use of pi-phase-shifted fiber Bragg gratings,” Optics Lett., Vol. 24, pp. 1091-1093, 1999.