|
FEM for electromagnetic simulation with absorbing boundary condition is applied to the design of polarizers, and the characteristics of metal sheet polarizers has been studied numerically. The dimensions of Au and Al metal sheet polarizers, which give enough performance as practical polarizers with much thinner structure than conventional polarizers, are presented. An Al metal sheet polarizer with comparable performance to Au metal sheet polarizer can be achieved by applying thinner Al metal sheets than the thickness of Au metal sheets. However, the performance given by Al metal sheet polarizer should be taken care, because the relative permittivity of Al film varies largely according to the film condition. Though Au and Al metal sheet polarizers exhibit high performance, the reflectance of TE polarization is higher than that of conventional polarizers. Therefore, the stray light should be paid attention more than conventional ones. The metal sheet polarizer exhibits enough high polarization performance for wide range of wavelength over 5 times as large as the distance between the metal sheets. The characteristics of metal fiber polarizers are also simulated. The metal fiber polarizers need much finer and thicker structure than metal sheet polarizers to exhibit enough performance.
|
