Spr Sensing Technology To Detect Wavelength

Surface Plasmon oscillation is a phenomenon of physical optics, Evanescent Wave produced in the boundary of glass when Total Internal Reflection occur can be used to excitate the free charges at a metal surface to form Surface Plasma Wave which can propagate along a metal-media interface. In the condition of proper incidence angle or wavelength, frequency and wavevector of Surface Plasma Wave are equal to Evanescent Wave, resonance occur. It is also be called Surface Plasmon Resonance. Here, incidence light is absorbed, energy of the reflection light decrease rapidly. Surface Plasma Wave light modulator just modulate with this theory. Surface Plasmon Resonance has two kind of modulation couple mode, one is prism-metal-vacuum Kretschmann configuration, the other is prism-vacuum-metal Otto configuration, experiment adopted Otto configuration. 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 physical quantities corresponding to the change of refractive indices. SPR technology is widely utilized in the field of biochemistry,immunology and Pharmacy etc.This paper first recalled the development history of the theory and practical application of surface plasma resonance (SPR), and analysed the common SPR sensor-based system and properties. In the second chapter, from the principle of the electrokinetic and physical optics, optical reflection law, refraction law and total reflection law are explicately deduced. Taking account of the properties of the metal plasma, the oscillation principle and optical waves excitation of the metal plasma were studied, then the resonance condition and formulas of the reflective index of metal surface plasma were derived , which provide theoretical supports for design and application of SPR sensor. During the third chapter ,based on the study of the Kretschmann prism , the structure,classification and common test method of Kretschmann prism were detailedly introduced. Besides, fabrication technique was also briefly presented .In the fourth chapter, specific experimental instruments and experimental process to detect the wavelength of light source by employing SPR sensor-based system were introduced, the concrete parameters and properties were also listed. The experiment was used of angular adjusting method, broadband source was detected, then the wavelength resolution of the system was calculated and draw the experimental curve. Compared with theoretical data, give the conclusion of the experiment. In the end, the summary and the development prospect of this subject were discussed. At the same time, the deficiencies of this subject was generalized; directions of the further study, application and improvement of this subject were presented.In a word, the further study about sensor theory based on SPR effect were carried out ,the Kretschmann prism SPR sensor manufactured by the previous experience, and the angular adjusting SPR sensor-based system built. At the same time, the test method to wavelength of the source was designed and realized, which provides novel thought to optical wavelength demodulation, optical information processing and optical detection.