Research For High-resolution Sensor System Based On Refractive Index Detection

In the era of digital information,everything has become a trend of interconnection.Hence,the intelligence fields,such as intelligent hardware,smart factories and intelligent cars,have also been rapid development.The research and application of sensors are the technological basis and the pioneer in realizing ‘everything of Internet'.It is also the most important research direction in these intelligence fields.But the domestic sensor accuracy of measurement,resolution,stability,response time,temperature characteristics,and other indicators have a considerable gap compared to the similar products of foreign countries.In this paper,we designed a high-resolution multi-channel sensor system based on refractive index detection.It is compatible with two types of sensing structures,one is total reflection type and the other is surface plasmon resonance(SPR).We can choose the corresponding sensing structure to accommodate different application scenarios.In order to improve the resolution of the system,we optimize the system from both the device and the algorithm.On the system,we analyze the contradiction between signal-to-noise ratio and pixel sensitivity,and balance the restraint of the system resolution by iterative experiments.On the algorithm,we adopted the row average,polynomial fitting method and sliding point averaging method to reduce the system noise.So the system performance can reache the optimal state.The total reflection sensor refractive index resolution grow to 78.13 10 RIU-? after optimized.The optimized SPR sensor refractive index resolution increase to 89.29 10 RIU-?.We find that the total reflection sensor is suitable for low-cost and high-accuracy bulk refractive index measurement through theoretical analysis and calculation.The SPR sensor has a high surface sensitivity and is suitable for the detection of multi-layer molecules.We used the sensors for chemical and biological experiments.In view of the advantages of high refractive index resolution and corrosion resistance of the total reflection sensor,the valence state of the vanadium ion in the vanadium battery electrolyte is reduced from pure five to pure two by the monitoring battery detection system.The result show that the application of the total reflection sensor in the chemical monitoringis is feasibility.And the average valence of vanadium ion measured by the experiment is 0.00 54%,which is one order of magnitude higher than the existing detection methods and is in an international leading position.Furthermore,according to the different interface properties of SPR sensor,we utilized the characteristics of dopamine adhesion and modification to bio-detecte and functionalize the sensor chip,and monitored to the specific binding process between rabbit immunoglobulin and staphylococcus protein A.The two kinds of biological molecules specific binding changing can be seen clearly in the results of experiment.And the consequence verify that SPR sensor can apply to biological detection.In this paper,we use single-layer gold film as sensor structure,the detection sensitivity and refractive index resolution index of the sensor reached the mainstream of the SPR level.The sensors greatly reduce costs,and have great commercial potential.