The reflection and transmittance of s-and p-polarized lights should be treated separately at nonzero angle incidence.By choosing two special film materials whose refractive indices meet the Brewster condition in a given incident angle,the reflection of p-polarized light can be eliminated.When the two materials are fabricated into multilayer stacks,the reflection of s-polarized light can be largely increased while the reflection of p-polarized light keeps low.According to this principle,a film polarizer with bandwidth of 198 nm or even more is designed. The reflection and transmittance of s-and p-polarized lights should be treated separately at nonzero angle incidence. By choosing two special film materials whose refractive indices meet the Brewster condition in a given incident angle, the reflection of p-polarized light can be eliminated .When the two materials are fabricated into multilayer stacks, the reflection of s-polarized light can be increased greatly while the reflection of p-polarized light keeps low. According to this principle, a film polarizer with bandwidth of 198 nm or even more is designed.