A sub-wavelength grating planar metal lens which can enable both polarization information acquisitioning and light’s focusing is designed based on the principle of insect polarization vision in order to use the all-weather polarized light information in the daytime and night efficiently

expanding the application of polarized light navigation system in low-light environment. Based on the theory of surface plasmon polaritons

design a new subwavelength nanoscale grating polarizing concentrator by the structure of variable spacing w and variable height d nano metal grating array structure

use the finite-difference time-domain（ FDTD） method to simulate on structure parameters of concentrator by optimized analysis on light field distribution

influence rule of each parameter on focus position and focusing effect is given. Transmittance of TM light is solved. The focus of the optimal structure is located in the light outlet 2 798 nm of the polarizing concentrator. The light intensity is increased to 16 times. Transmittance of the polarizer is about 63 % in the 450 nm which is sensitive band of the polarized light navigator. This structure provides an effective reference for optical design of micro nano polarization navigation devices in the future and integrated fabrication.