According to the rigorous coupled wave theory and the equivalent medium theory

we propose a design and simulation methods for a sub-wavelength guided mode resonant grating filter based on the alumina material.The reflection spectrums of alumina grating in strong and weak modulation system are simulated and analyzed by Rsoft.Also

the influence of structural parameters such as grating period（400～420 nm）

duty ratio（0.2～0.8）and grating thickness（117～367 nm）on the spectral characteristics of grating are investigated.The simulation results indicate that the alumina grating has excellent filtering effect at 610 nm wavelength with the side band less than 3%

FWHM <0.3 nm and high reflectivity（close to 100%）.Finally

we fabricated a alumina resonance filter in the spectral region by fast atom beam etching technology.