Design And Preparation Of Polarized Light Sensitive Unit Of Imitation Mantis Shrimp

Bionic polarized light navigation based on natural polarization characteristics is a new type of autonomous navigation technology,which has attracted much attention in recent years because of its advantages of high accuracy,strong anti-interference capability,full autonomy,and good real-time performance.However,the application of bionic polarized light navigation has not yet reached a high level due to the limitation of devices.Polarized light sensitive unit is the key device in a polarized light navigation system,and excellent performance of polarizer and photodetector can effectively improve the accuracy and reliability of navigation system.Biological studies have found that mantis shrimp has a powerful visual system that can achieve high quality polarization information detection.Therefore,in this paper,we propose a design and preparation method of a polarized light sensitive unit imitating mantis shrimp based on the study of the polarization imaging and spectral detection mechanism of mantis shrimp,and analyze the feasibility of the proposed method through relevant experiments and discussions.The main research content and related work are as follows.(1)Starting from the mantis shrimp and its compound eye optical structure and polarization spectral function,we conducted an in-depth study on its polarization spectral mechanism and polarization information processing mechanism,and proposed an implementation method of a polarization-sensitive cell mimicking the compound eye of the mantis shrimp inspired by its polarization function,and formed a specific design scheme of the mimicking polarization-sensitive cell polarizer and the mimicking photodetector of the photoreceptor.(2)By studying the basic theory of nanometer metal grating polarizer and the calculation method of subwavelength metal grating,we propose a design method of high-performance subwavelength polarizer based on the "sandwich" substrate structure by imitating the functional mechanism of the mantis shrimp polarization sensitive cells to address the problems of low extinction ratio and high price of traditional wire grating polarizer.The results show that the polarizer has a good performance with an extinction ratio of more than 90 d B in the visible wavelength range and a TM transmittance of more than 30%,which can well meet the demand for high extinction ratio and large bandwidth in polarized light navigation applications.In addition,the superiority and feasibility of the proposed method are further demonstrated in terms of polarization transmittance properties and error tolerance.(3)For the above designed high performance subwavelength metal grating polarizer,the research work of nano-grating structure process and performance testing was carried out.Firstly,by studying the thermal nanoimprinting technology and UV-curable nanoimprinting technology,we propose and realize the preparation method of subwavelength metal grating polarizer,and the SU5000 scanning electron microscope observation results show that the grating structure is obvious and flat.Based on this,a performance test system of subwavelength metal grating polarizer is designed for the testing of polarizer performance indexes such as transmittance and extinction ratio.(4)By studying the basic theory of photodetector and performance parameters such as spectral response range,a multispectral photodetector with a simple structure based on stacked PN junctions is designed for the problems of small detection range,low detection efficiency and slow response speed of existing photodetectors,following the functional mechanism of mantis shrimp photoreceptor cells.On the one hand,Silvaco TCAD software is used to simulate and calculate it,and the results show that its quantum efficiency is up to 70% and its response is up to 0.32 A/W,which can meet the requirements of fast response and high efficiency of photodetectors in applications such as polarized light navigation;on the other hand,the results of comparison with other commercial products and research models show that this photodetector has excellent overall performance.