Linear Polarized Light Image Acquisition And Processing System Based On FPGA

As a new type of detection technology,polarization detection technology has been gradually applied in various fields and plays an irreplaceable role.Polarization detection technology is mainly divided into polarization imaging technology and polarization measurement technology.Among them,polarization imaging technology is mainly used in military target recognition and detection imaging in the aerospace field.Polarization measurement technology is mainly used in the detection of blood glucose concentration in the medical field and the detection of glucose concentration in the industrial field.Combined with the characteristics of optically active medium solution and the principle of optical rotation of polarized light,scientists have developed a polarimeter that reads the rotation angle manually,but this manual reading method inevitably has errors caused by the human eye.In this paper,in order to overcome the error caused by human eye reading and calculate the degree of rotation of linearly polarized light more conveniently,based on the understanding and mastery of FPGA,CMOS image sensor,and linearly polarized light imaging,an FPGA-based linearly polarized light image acquisition and processing is designed.The system is used for the collection,display,storage and processing of linearly polarized light images.This design mainly uses FPGA as the main control chip,drives the CMOS image sensor to collect linearly polarized light images,displays the collected images on the LCD screen in real time,monitors the changes of the collected images in real time,and uses the buttons to control the collection and upload of a frame of image.A frame of image collected is stored in the SD card,and the image is uploaded through the UART serial port,and the image data is processed through the MATLAB processing system.The whole system includes: image optical path system,FPGA image acquisition system,MATLAB processing system.For the image optical path system,a more suitable semiconductor laser is selected to ensure the uniformity of the beam and the best image quality.A more precise polarizer is selected to facilitate the comparison and verification of experimental results.The hardware circuit of the FPGA image acquisition system is designed by analyzing the functional requirements.The software part is designed and debugged under the Quartus II development platform,and the functions of the hardware circuits of each module are integrated and used.The MATLAB processing system designs a complete set of processing programs according to the characteristics of the collected images.This design improves the traditional method of measuring the rotation angle of linearly polarized light,and improves the accuracy and stability of the measurement.It is a useful attempt for the automatic measurement of optical rotation in the future,and is conducive to the development of optical rotation-related measuring instrument.