Research On Optical Fiber Surface Plasmon Wave Resonance Sensor Based On Built-in Modulation Layer And Its Spectrum Signal Processing

Surface Plasmon Resonance Sensor is a kind of optical sensor parts with high refractive indexoptical waveguide and precious metal film. Because of high sensitivity, anti-jamming, fast response,nondestructive, and many other advantages, SPR sensor has great development potential in many fieldssuch as biological medicine, environmental monitoring and food sanitation.In order to improve the overall performance of optical fiber SPR sensor, increase the applicationfield of optical fiber SPR sensor and improve a wide range of practical application, this paper researchcontent includes following several parts:First, principle and conditions of plasma wave interacting excitation SPR effect between opticalfiber and metal surface. The finite difference time domain numerical simulation is provide by Optiwaveaiming at light energy transmission distribution of inside, outer layer modulation layer and compositeresonance film optical fiber SPR sensor.Secondly, an optical fiber SPR sensor model based on internal modulation layer structure ispresented, also a liquid refractive index detection system based on this sensing model is built up. Aphotoelectric composite film with unique performance can be constitute by overlap different thicknessand attributes optical transparent film between gold film and fiber core as internal modulation layer. Itcan adjust evanescent wave vector and plasma wave vector at surface of gold film at the same time.Model use resonance mechanism can not only adjust resonance spectrum offset range, but also providethe prove for the realization of sensor sensitivity. The optical fiber SPR sensor probe with modulationlayer structure is developed to investigate the temperature sensitive characteristic.Finally, the noise simulation resonance signal and actual measurement income resonance spectrumsignal are suggested to do the noise reduction filtering with threshold wavelet packet decompositionbased on noise source attribute analysis of optical fiber SPR resonance spectrum signal. The resultsshow that the signal noise can be effectively filtered, resonance spectrum feature information can beeffectively extracted.