Study On Optical System Of Underwater Bionic Polarization Imaging

Underwater optical imaging is a very meaningful work,it has a broad application background in the fields of underwater target detection and marine exploration.Being influenced by the inherent properties of water,when the traditional photoelectric device detects underwater targets,it will be affected by the absorption and scattering of the water body,and will attend to the severe attenuation,resulting in low contrast imaging of the underwater target,blurred images,and the distance is limited.Therefore,how to improve the underwater optical imaging system,improve the imaging quality and enhance the underwater detection capability has become a issue of great research significance.In view of the above problems,this thesis designed a new type of underwater bionic polarized imaging optical system based on the National Natural Science Foundation project of " Research on Underwater Polarization Imaging Based on Bionic Visual information Fusion ",combined with the mantis shrimp compound eye polarized structure and polarized imaging principle.The main research contents of this article are as follows:Firstly,by researching the structure of the compound eyes of Praying Mantis Shrimp and the principle of its intuitive mechanism of polarization perception,the polarization characteristics of light and its characterization method are introduced,and the polarization imaging model and the imaging principle are introduced.Then compares and analyzes the work of existing polarization imaging systems principles and their advantages and disadvantages.According to the requirements of bionic structure,a split-aperture four-channel array simultaneous polarization imaging system is proposed.The system consists of a front common aperture group and four centrifugal axis eccentric sub-aperture systems at the rear,which has a compact structure and can realize real-time polarization parameter image acquisition of underwater targets.Secondly,this thesis studies the propagation characteristics of light waves in water bodies,including the attenuation,and absorption characteristics of water to light,the scattering characteristics of water to light,and the influence of light refractive index,which is the physical basis of underwater imaging.By establishing the relationship between evaluation parameters and imaging quality,analyzed the advantages of two types of active polarization imaging,linear polarization and circular polarization,for underwater imaging.Simple experiments show that polarization technology can improve the imaging quality of underwater targets.Finally,this thesis utilizes ZEMAX optical design software to design a new type of bionic underwater real-time polarization imaging detection optical system.The design mainly includes the calculation of the ideal optical parameters of the optical system,the construction of the initial structure,the optimization of the system image quality and the evaluation of the image quality.Through the formulation and analysis of the tolerance of the optical system,the feasibility of the actual lens processing and possibility of adjustment of the system was verified,and the corresponding optomechanical structure was designed.