Research On Concentration Measurement Of Optical Media Solution Based On FPGA

The measurement of the concentration of polarimetric medium solution plays an important role in many fields,and the lactose content of dairy food can be well monitored in terms of diet,which can effectively reduce the phenomenon of "lactose intolerance".In medicine,the blood glucose concentration of the human body can be monitored,and timely drug intervention can be made for diabetic patients,which can play a key role in later treatment.Quality control can be carried out in beverage production,and it also has certain significance in agriculture.It is known that the proposed study of polarimetric concentration measurement is inseparable from human eye readings or PC-side processing.In order to make up for the error of human eye reading and speed up the processing speed,this paper designs a polarimetric medium solution measurement system based on FPGA platform on the basis of understanding the characteristics of FPGA and linear polarized light imaging,which mainly includes two parts optical path system and FPGA processing system.In terms of optical path system,a double optical path system with spatially symmetrical structure is designed to reduce the error caused by external factors,and the polarization direction of linear polarized light can be changed by using the optical rotation medium solution,and presents a linearly polarized light image through an angularly polarized display for use by FPGA processing systems.The hardware architecture of the FPGA processing system is OV5640 camera image acquisition,DDR3 cache image data,FPGA image preprocessing and concentration detection algorithm implementation,and LCD display real-time image and processed data.On this basis,the characteristics of the linear polarized light image and the initial image RGB565 format acquired by the camera are analyzed,and in order to reduce the difficulty of image processing in FPGA,three image preprocessing methods are carried out: grayscale,binary value and morphology.According to the image characteristics,the algorithm for finding the polarization direction in concentration detection is determined,and the zero,first-order moment and second-order center distance of the image are determined,and the formula derives the directional characteristics of the second-order central moment and the relationship between concentration and polarization direction angle.According to the determined algorithm principle and various peripherals,the development and debugging of each module was completed on the VIVADO platform,the system was built for functional verification and the data required for the experiment was measured,and the maximum error between the measured concentration and the actual concentration was 3.774%.The experimental results show that the system function is correct and has greatly improved the real-time performance,which is of great significance to the development of miniaturization of optical rotation medium solution concentration measurement instruments.