Design And Performance Of An Optical Fiber Based Surface Plasmon Resonance Sensor

Surface plasmon resonance (SPR) sensor is a new transducer with high precision, which is mainly used in fields such as biological detection, drug screening and environmental monitoring. SPR sensor has many advantages, e.g., convenient, no-labeled, non-invasive and high-sensitivity. Combining with some coupling mediums and detection methods, the sensor can be used for real-time monitoring. Three main modulating methods based on angle, wavelength, and phase can be used for SPR detection. According to different coupling mediums, the sensor can also be divided into prism, optic fiber, and grating types. In order to realize the researching object, an optic fiber SPR sensor and a detection system based on it are mainly studied.In this paper, some concepts about the SPR sensor are introduced at first. The theoretical analysis of the condition to induce SPR phenomenon has been carried out. The structure and working principle of the prism based SPR sensor is presented, and on this basis the structure and working principle of optic fiber based SPR sensor is introduced. In order to overcome the shortcoming of existing optic fiber based SPR sensors, a new design is presented. The structural parameters of this new device are decided by theoretical analysis, and the structure of the optic fiber is also rebuilt. A detection system including optical components, software, hardware, and MATLAB data processing, is set up based on this sensor. This system can detect the change of environmental media by analyzing the light spectrum. Optical match system is used to adjust the chaotic light from the source and couple it into optic fiber. The software is used to harmonize the working of different modules and process the data preliminary, including noise filtering, information extracting, curve drawing, and data storing. The hardware is used to control all components such as halogen tungsten lamp, peristaltic pump, spectrograph, and electric circuit. The MATLAB data processing is used for filtering waveform.The study about the optic fiber SPR sensor and it based detection system can form the foundation for its improvement, application, and production.