In order to resolve atmospheric optics polarization pattern for accurate navigation

a sub-wavelength metallic polarizer is designed based on rigorous coupled-wave analysis（ RCWA）

which is suitable for structure of compound eye. Aiming at single and bi-layer metallic grating with different period

duty cycle and metal layer thickness are simultated and analyzed

actual technological level and cost into consideration

bi-layer metallic grating with period of 200 nm

duty cycle of 0. 5 and metal layer thickness of 100 nm is chosen for polarizer of compound eye

TM polarized light transmittance of blue light in central band 450 nm of the designed bi-layer metallic grating achieve 45 %

and the extinction ratio achieve 450

satisfy requirements for polarization navigation.