单模偏芯光纤折射率传感器研究
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摘要
相比传统的传感器,光纤传感器具有许多独一无二的优点,在许多领域有着广泛研究与应用。光纤干涉型传感器具有高灵敏度等优点而成为光纤传感器最实用的一种。基于迈克尔逊干涉原理的光纤传感器具有制作简单、测量便利等优点而成为光纤干涉型传感器研究中很常见的一种。光纤折射率传感器具有较大的应用价值,主要在生物、化学、医药等领域应用较为广泛。
一种基于迈克尔逊干涉原理的新型光纤传感器在本文中得到了实现,叫单模偏芯光纤折射率传感器,通过偏芯将光从纤芯耦合到包层中。借助光束传播法(BPM),得出了外界环境折射率与包层模的有效折射率关系以及基模与部分包层模间的耦合关系。理论结果表明：随着外界环境折射率值的增大,基模的有效折射率保持不变,而包层模的有效折射率值则逐渐变大,当外界环境折射率的值接近包层折射率时,包层模的有效折射率值变化越明显；随着偏心距离的增大,基模的耦和效率迅速变小,而包层模的耦合效率逐渐变大,最后趋向一个定值。特征波长随着外界环境折射率的增加而向减小的方向移动。
利用实验中制作的单模偏芯传感器相继对溶液折射率测量、结构的温度敏感性和折射率测量的温度补偿效应进行了实验研究。实验结果与理论分析基本一致,液体折射率与特征波长有着单调的递减关系,而温度与特征波长有着很好的线性关系。实验中能够通过温度实验来实现一定程度的温度补偿,以减小温度对折射率测量的影响。
With many unique advantages compared to traditional sensors, optical fiber sensors have been studied and applied to many different areas. Interferometric sensors are one of the most useful sensor types due to their high sensitivities and relatively relaxed requirement on the stability of the optical source's power level. Optical sensors based on the principle of Michelson interferometer are one of the most popular sensor types due to their simple-structure and measurement facilities. Fiber refractive index sensors have so many available applications extremely in the field of biology, chemistry, medicine and so on.
Based on the principle of Michelson interferometer, a new kind of optical sensor is developed. We call it single-mode core-offset optical sensor which couple light from core to cladding to replace LPG. We get the relationship between surrounding RI and cladding's effective RI with BPM. The coupling coefficients between core and cladding modes are calculated by it too. The results show that the effective RI of the cladding mode increases while the surrounding RI increasing and the effective RI of the core mode stays almost at constant; each mode's coupling efficiency changes gradually and finally reaches a fixed value with the increasing of core-offset distance. The characteristic wavelength will shift to short wavelength direction when the surrounding RI increases.
The experiment results include three parts:the result of sugar solution's RI, the result of aqueous solution after temperature compensation and the result of high temperature. The result fit well with theoretical analysis, Experimental results show that there will be an increasing relationship between characteristic wavelength and temperature. There will be a better decrease gradually relationship between characteristic wavelength and refractive index after temperature compensation.
一种基于迈克尔逊干涉原理的新型光纤传感器在本文中得到了实现,叫单模偏芯光纤折射率传感器,通过偏芯将光从纤芯耦合到包层中。借助光束传播法(BPM),得出了外界环境折射率与包层模的有效折射率关系以及基模与部分包层模间的耦合关系。理论结果表明：随着外界环境折射率值的增大,基模的有效折射率保持不变,而包层模的有效折射率值则逐渐变大,当外界环境折射率的值接近包层折射率时,包层模的有效折射率值变化越明显；随着偏心距离的增大,基模的耦和效率迅速变小,而包层模的耦合效率逐渐变大,最后趋向一个定值。特征波长随着外界环境折射率的增加而向减小的方向移动。
利用实验中制作的单模偏芯传感器相继对溶液折射率测量、结构的温度敏感性和折射率测量的温度补偿效应进行了实验研究。实验结果与理论分析基本一致,液体折射率与特征波长有着单调的递减关系,而温度与特征波长有着很好的线性关系。实验中能够通过温度实验来实现一定程度的温度补偿,以减小温度对折射率测量的影响。
With many unique advantages compared to traditional sensors, optical fiber sensors have been studied and applied to many different areas. Interferometric sensors are one of the most useful sensor types due to their high sensitivities and relatively relaxed requirement on the stability of the optical source's power level. Optical sensors based on the principle of Michelson interferometer are one of the most popular sensor types due to their simple-structure and measurement facilities. Fiber refractive index sensors have so many available applications extremely in the field of biology, chemistry, medicine and so on.
Based on the principle of Michelson interferometer, a new kind of optical sensor is developed. We call it single-mode core-offset optical sensor which couple light from core to cladding to replace LPG. We get the relationship between surrounding RI and cladding's effective RI with BPM. The coupling coefficients between core and cladding modes are calculated by it too. The results show that the effective RI of the cladding mode increases while the surrounding RI increasing and the effective RI of the core mode stays almost at constant; each mode's coupling efficiency changes gradually and finally reaches a fixed value with the increasing of core-offset distance. The characteristic wavelength will shift to short wavelength direction when the surrounding RI increases.
The experiment results include three parts:the result of sugar solution's RI, the result of aqueous solution after temperature compensation and the result of high temperature. The result fit well with theoretical analysis, Experimental results show that there will be an increasing relationship between characteristic wavelength and temperature. There will be a better decrease gradually relationship between characteristic wavelength and refractive index after temperature compensation.
引文
[1]廖延彪.光纤光学：原理与应用[M].北京：清华大学出版社,2010.
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[4]李文植.光纤传感器的发展及其应用综述[J].科技创业月刊.2005,18(7)：153-154.
[5]李强,王艳松,刘学民.光纤温度传感器在电力系统中的应用现状综述[J].电力系统保护与控制,2010,38(1)：135-140.
[6]罗彬彬,赵明富,周晓军等.高斯切趾光纤Bragg光栅折射率传感器特性研究[J].光电子激光,2011,22(2)：201-206.
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[22]于清旭,贾春艳.膜片式微腔F-P腔光纤压力传感器[J].光学精密工程,2009,17(12)：2887-2892.
[23]刘跃辉,张旭苹,董玉明.光纤压力传感器[J].光电子技术,2005,25(2)：124-132.
[24]姚骏,付敬奇,张承燕等.光纤流量传感器的进展[J].传感器技术,2002,21(3)：1-7.
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[29]Anbo Wang, Se He, Xiaojan Fang, et al. Optical Fiber Pressure Sensor Based on Photoelasticity and its Application[J]. Journal Of Lightwave Technology,1992,10(10): 1466-1472.
[30]Farnoosh Rahmatian, Abraham Ortega. Applications of Optical Current and Voltage Sensors in High-Voltage Systems[C]. IEEE PES Transmission and Distribution Conference, Exposition Latin America, Venezuela,2006,1-4.
[31]陈新,李维晖,张宏.用分光计测液体折射率[J].现代科学仪器,2006,2：93-95。
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[33]金清理,柯见洪.用掠入射法测量液体折射率和浓度[J].实验室研究与探索,2002,21(3)：52-55.
[34]胡晓伟.基于CMOS图像传感器的液体折射率研究[D].硕十学位论文,浙江大学,2005.
[35]David Monzon-Hernandez, Joel Villatoro. High-resolution refractive index sensing by means of a multiple-peak surface Plasmon resonance optical fiber sensor[J]. Sensors and Actuators B,2006,115(1):227-231.
[36]Hyungduk Ko, Jun Kameoka, et al. Measurements of refractive index change due to positive ions using a surface plasmon resonance sensor [J]. Sensors and Actuators B,2009, 143(1):381-386.
[37]Jimmy Castillo, Hector Gutierrez, Jose Chirinos, et al. Surface Plasmon resonance device with imaging processing detector for refractive index measurements[J]. Optics Communications.2010,283(20):3926-3930.
[38]Anuj K. Sharma, Rajan Jha, and B. D. Gupta. Fiber-Optic Sensors Based on Surface Plasmon Resonance:A Comprehensive Review [J]. IEEE Sensors Journal,2007,7(8):1118-1129.
[39]Guanghui Wang, Perry Ping Shum, Ho-pui Ho, et al. Modeling and analysis of localized biosensing and index sensing by introducing effective phase shift in microfiber Bragg grating (μFBG)[J]. Optics Express.2011,19(9):8930-8939.
[40]YUN Bin-feng, CHEN Na, CUI Yi-ping. Refractive index sensing characteristics of fiber Bragg grating based on cladding mode[J]. Acta Photonica Sinica,2006,26(7):1013-1015.
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[2]何慧灵,赵春梅,陈丹等.光纤传感器现状[J].激光与光电子学进展.2004,41(3)：39-41.
[3]廖延彪,黎敏.光纤传感器的今日与发展[J].传感器世界,2004,2(10)：6-12.
[4]李文植.光纤传感器的发展及其应用综述[J].科技创业月刊.2005,18(7)：153-154.
[5]李强,王艳松,刘学民.光纤温度传感器在电力系统中的应用现状综述[J].电力系统保护与控制,2010,38(1)：135-140.
[6]罗彬彬,赵明富,周晓军等.高斯切趾光纤Bragg光栅折射率传感器特性研究[J].光电子激光,2011,22(2)：201-206.
[7]张桂菊,于清序.应用于高温高压测量的非本征光纤法布里-伯罗传感器系统研究[D].大连理工大学博士学位论文,2005.
[8]周智,边玉明,田石柱.土木工程健康监测用F-P光纤应变测量技术[J].传感器技术,2001,20(4)：9-13.
[9]杨要恩,孙宝臣,于庆敏.基于白光干涉的应变式F-P光纤传感器的研究[J].石家庄铁道学院,2005,18(1)：47-49.
[10]曹振新,梁大开.表面等离子体波传感器特性的研究及其应用[D].南京航空航天大学硕士学位论文,2002.
[11]黄俊,赵文琪.高精度光纤生物传感器的研制[J].武汉理工大学学报,2010,32(21)：115-117.
[12]M.E.Bosch, A. J. R. Sanchhez, F. S. Rojas, et al. Recent development in optical fiber biosensors [J]. Sensors,2007,7(6):797-859.
[13]Jie Lin. Recent development and applications of optical and fiber-optic pll sensors[J]. Trend in analytical chemistry,2000,19(9):541-552.
[14]吴锁柱.新型模式滤光光纤化学传感器的研究[D].硕十学位论文,山西大学,2009.
[15]庞全.基于特征光谱识别的光纤化学传感技术[J].仪器仪表学报,2001,22(6)：588-591.
[16]Robert Bogue. Optical chemical sensors for industrial applications[J]. Sensor Review,2007,27(2):86-90.
[17]Colette McDonagh, Conor S. Burke, Brian D. MacCraith. Optical Chemical Sensors[J]. Chem. Rew,2008,108(2):400-422.
[18]D. Allen, S. M. Bennett, J. Brunner, et al. A low cost fiber optic gyro for land navigation[J]. Proc. SPIE Fiber Optic and Laser Sensors X11,1994,2292:203-217.
[19]J. A. Bucaro, H. D. Dardy, E. F. CarDme. Fiber-optic hydrophone [J]. Acoust. So c. Am,1977,62(5):1302-1304.
[20]张桂菊,于清旭,宋士德.基于F-P腔的干涉/强度调制型光纤温度传感器[J].中国激光,2005,32(2)：228-231.
[21]李强,王艳松,刘学民.光纤温度传感器在电力系统中的应用现状综述[J].电力系统保护与控制,2010,38(1)：135-140.
[22]于清旭,贾春艳.膜片式微腔F-P腔光纤压力传感器[J].光学精密工程,2009,17(12)：2887-2892.
[23]刘跃辉,张旭苹,董玉明.光纤压力传感器[J].光电子技术,2005,25(2)：124-132.
[24]姚骏,付敬奇,张承燕等.光纤流量传感器的进展[J].传感器技术,2002,21(3)：1-7.
[25]胡玉瑞,唐源宏,李川.光纤Bragg光栅流量传感器[J].传感技术学报,2010,23(4)：471-474。
[26]V. Kleiza, J. Verkelis. Some Advanced Fiber-Optic Amplitude Modulated Reflection Displacement and Refractive Index Sensors[J]. Nonlinear Analysis:Modeling and Control,2007,12(2):213-225.
[27]Minho Optics, Shizhuo Yin, Paul B. Ruffin. Fiber Bragg Grating Strain Sensor Demodulation with Quadrature Sampling of a Mach-Zehnder Interferometer[J]. Applied Optics,2000,39(7):1106-1111.
[28]A. D. Kersey, T. A. Berkoff, W. W. Morey. High-resolution fibre-grating based strain sensor with interferometric wavelength-shift detection[J]. Electronics Letters,1992, 28(3):236-238.
[29]Anbo Wang, Se He, Xiaojan Fang, et al. Optical Fiber Pressure Sensor Based on Photoelasticity and its Application[J]. Journal Of Lightwave Technology,1992,10(10): 1466-1472.
[30]Farnoosh Rahmatian, Abraham Ortega. Applications of Optical Current and Voltage Sensors in High-Voltage Systems[C]. IEEE PES Transmission and Distribution Conference, Exposition Latin America, Venezuela,2006,1-4.
[31]陈新,李维晖,张宏.用分光计测液体折射率[J].现代科学仪器,2006,2：93-95。
[32]花世群,骆英,洪云.基于等厚干涉原理的液体折射率测量方法[J].中国激光,2006,33(11)：1542-1546.
[33]金清理,柯见洪.用掠入射法测量液体折射率和浓度[J].实验室研究与探索,2002,21(3)：52-55.
[34]胡晓伟.基于CMOS图像传感器的液体折射率研究[D].硕十学位论文,浙江大学,2005.
[35]David Monzon-Hernandez, Joel Villatoro. High-resolution refractive index sensing by means of a multiple-peak surface Plasmon resonance optical fiber sensor[J]. Sensors and Actuators B,2006,115(1):227-231.
[36]Hyungduk Ko, Jun Kameoka, et al. Measurements of refractive index change due to positive ions using a surface plasmon resonance sensor [J]. Sensors and Actuators B,2009, 143(1):381-386.
[37]Jimmy Castillo, Hector Gutierrez, Jose Chirinos, et al. Surface Plasmon resonance device with imaging processing detector for refractive index measurements[J]. Optics Communications.2010,283(20):3926-3930.
[38]Anuj K. Sharma, Rajan Jha, and B. D. Gupta. Fiber-Optic Sensors Based on Surface Plasmon Resonance:A Comprehensive Review [J]. IEEE Sensors Journal,2007,7(8):1118-1129.
[39]Guanghui Wang, Perry Ping Shum, Ho-pui Ho, et al. Modeling and analysis of localized biosensing and index sensing by introducing effective phase shift in microfiber Bragg grating (μFBG)[J]. Optics Express.2011,19(9):8930-8939.
[40]YUN Bin-feng, CHEN Na, CUI Yi-ping. Refractive index sensing characteristics of fiber Bragg grating based on cladding mode[J]. Acta Photonica Sinica,2006,26(7):1013-1015.
[41]K.S.Chiang, Y.Liu, M. N.Ng, et al. Analysis of etched long-period fibre grating and its response to external refractive index[J]. Electron. Lett,2000,36(11):966-967.
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