Design On Key Techniques Of Liquid Refractive Index Based On Prismatic Optical Fiber Sensor

Concentration is an important parameter on characterizing the properties of the liquidmedium.In the basic research, chemical analysis, pollutants detection, diagnostics, food andsemiconductor manufacturing in fields of liquid concentration to precise measurement. Manydevelopment and products in the process of the final measure, similar to the refractive indexand light absorption measurements optical instruments by more and more application, ofwhich use to measure the concentration of the refractive index liquid became a veryconcerning field, on many occasions, the index of refraction of the measurement be testing thewater and some other solution concentration of an ideal method. The same some chemicalmethod than the simple and cheap, and do not change the solution nature itself.First of all, this design from the refractive index with solution concentration relationship,we analyzed the refractive index method of measuring solution concentration developingsituation of domestic and foreign, determine the measured data and the correspondingmeasuring method.Finally, to build fiber-optic sensing system and emulation MCU the signal processingcircuit,and product PCB board, make the appropriate physical circuitry.Among,in the opticalfiber sensing system in the form of the dual optical path, After the light passes through theoptical switch, one way directly into the photoelectric conversion detectors, in addition toanother way through into a liquid refraction and then into a photodetector which is modelexactly the same, dual optical system can effectively reduce noise signal in the system,This isthe novelty of this design;Two optical pulse signal through the MCU processing circuit,respectively display the difference between the high and low of the voltage on LCD, Thencalculated the ratio of the pressure,The relationship between concentration and refractiveindex of the liquid and the pressure ratio,In order to obtain the concentration of liquid to bemeasured,Finally, the results of the experimental results with theoretical models to error analysis,verify the reasonableness of the design.