【作者】 刘耀波；

【导师】 刘月明；

【作者基本信息】 西安理工大学 ， 测试计量技术及仪器， 2009， 硕士

【摘要】 表面等离子体共振(Surface Plasmon Resonance, SPR)效应是一种发生在金属薄层与电介质分界面上的物理光学现象,由于其对金属表面电介质折射率的变化非常灵敏,可以用来实时检测电介质折射率及其相关物理量的变化,SPR技术正被广泛应用于生物化学、免疫技术、制药等领域。目前最为常用的SPR传感器是棱镜式传感器,这种传感器具有高精度的特点,然而体积大、成本高等缺点限制了其在现场监测、实时分析等方面的应用。针对这种情况,本文设计了一种具有体积小、成本低和灵敏度高等特点的D型光纤SPR传感器,并对其测量原理、结构参数及相位检测等内容进行了研究,主要内容从以下几个方面展开：首先,从麦克斯韦方程组出发推导平面电磁波在介质中的传播,分析了全反射中倏逝波的产生原因及特性。根据德鲁特方程及薄膜中电磁波的传播理论,详细分析金属中等离子体的特性,深层次揭示SPR产生机理。其次,研究了D型光纤SPR传感器的测量原理,讨论了其结构参数对传感器性能的影响,得到了具有最佳性能的传感器参数。此外,还对双金属合金技术在传感器上的应用进行了研究。再次,讨论和比较当前相位检测方法,确定本文采用共光路干涉成像检测方法来设计相位检测系统,并以干涉原理为基础详细讨论了这种方法的检测原理。此外,还详细分析了此系统中相位的调制与解调。最后,详细分析了折射率检测系统的功能,利用Visual C++完成了基于PC机的检测系统软件开发。本论文在详细分析SPR效应的基础上完成了对D型光纤SPR传感器结构参数的优化设计、传感器后续的相位检测光路及检测系统软件设计等内容,为进一步开发完整的检测系统奠定了基础。更多还原

【Abstract】 Surface plasmon resonance (SPR) is an optical phenomenon taking place on the interface of metal-dielectric medium. Because of sensitive response to the refractive indices of dielectric in contact with the metal surface, SPR sensors are used for monitoring the variation of refractive indices or related quantities. SPR technology is widely utilized in the field of biochemistry, immunology and pharmacy etc.Presently prism sensor is widely used because of good sensitivity, but the demerits such as large volume, high cost limit its application in field detection and real-time detection. According to this situation, we consider a SPR sensor based on D-type optical fiber in this paper. The proposed sensor can provide good sensitivity, which is small, simple and inexpensive. At the same time, the measurement principle, parameters optimization and phase detection were researched. Main contents in the paper are as follows:Firstly, we deduced the propagation of plane electromagnetic wave in medium from Maxwell’s equations. Furthermore, the production and characteristics of evanescent wave were analyzed. In terms of Drude equation and theory of electromagnetic wave propagating in thin film, we researched the characteristics of plasmon in metal and explain the cause of SPR.Secondly, the measurement principle of D-type optical fiber sensor was discussed. In pursuit of the best performance, we optimized the parameters of the sensor. In addition, we studied the performance of optical fiber sensor with bimetallic alloy as well.Thirdly, the current phase detection methods were discussed and the common path interferometry was adopted to detect the phase difference in this paper. Furthermore, the measurement principle of this method was discussed based on interference principle.Besides, we also analyze the phase modulation and demodulation.Finally, we analyzed the function of refractive indices detection system in detail and completed development of this system software by Visual C++.In this paper we have completed parameters optimization of sensor, design of phase detection system and development of system software, all of these lay a foundation for further development of entire detection system.更多还原