Study On Dynamic Range Regulation And Multi-channel Technology Of Optical Fiber SPR

P-polarized occurs total reflection at the glass with nanoscale metal film interface,the evanescent field will penetrate into the metal film,when the free electrons in the metal and the evanescent wave in equal frequency,both resonance will occur, total reflection condition will be destroyed,the incident light is absorbed by electrons of the metal surface,the energy of the reflected light will fall sharply,this is the SPR phenomenon.When the angle of incidence、optical wavelength are fixed,this phenomenon will entirely depend on the refractive index of the film environment medium, the refractive index of the sensor can be made.SPR sensor is characterized by high sensitivity,anti-electromagnetic interference,fast response,no need to tag samples, etc.In order to compensate for the interference of the background refractive index and the effective measurement of the specific binding,multi-channel SPR sensor needs to be urgently developed.At present, the research on the multi-channel technology of SPR is more common in the prism structure,but the research on optical fiber SPR is still rare.Compared with the prism. Optical fiber SPR sensing probe has the advantages of small size, can be directly immersed in the solution to be measured. In this paper, I carry out the exploration of optical fiber SPR multi-channel technology:1.A new distributed multi-channel optical fiber SPR sensor with different gold film thickness is proposed2.In-depth study of SPR sensing mechanism, fabrication of step mode fiber transmission SPR sensing probe with the use of optical fiber polishing technology.The influence of lateral tilt angle on the dynamic range and sensitivity of SPR probe is studied by means of experimental study.A novel distributed multi-channel SPR micro sensor based on side slope step mode fiber cascade is proposed.3.Study of optical fiber SPR wavelength division multiplexing (WDM) and time division multiplexing (TDM) technology,propose and make duplex fiber four-channel SPR sensor,core fiber utilizing time-division multiplexing technology (parallel) is divided into two, then,in every way,a double channel is realized by using wavelength division multiplexing technology (series).Wavelength division multiplexing technology is different from the angle of the single mode fiber taper angle structure,adjusting the incident angle of the light source,thereby adjusting the dynamic range of SPR,it overcomes the problem that the distributed optical fiber SPR sensor is difficult to produce two resonance valley which are easy to distinguish between the limited wavelength detection range.In summary,this paper presents a new distributed multi-channel optical fiber SPR sensor with different gold film thickness.A novel distributed multi-channel SPR micro sensor based on side slope step mode fiber cascade is proposed.Combined use of SPR wavelength division multiplexing and time division multiplexing technology in optical fiber, a dual core fiber four channel SPR micro sensor is proposed and fabricated.Effectively solve the practical problems of optical fiber SPR can not achieve multi-channel measurement.