Artificial Uniaxial And Biaxial Dielectrics With Use Of 2-Dimensional Subwavelength Binary Gratings
Abbreviated Journal Title
J. Opt. Soc. Am. A-Opt. Image Sci. Vis.
DIFFRACTIVE OPTICS; ARTIFICIAL MEDIUM; ANTIREFLECTION; BINARY GRATINGS; ANTIREFLECTION-STRUCTURED SURFACES; RELIEF GRATINGS; OPTICS; Optics
Two-dimensional symmetric and asymmetric subwavelength binary gratings are investigated. A method for determining the three effective indices of a two-dimensional (2-D) subwavelength grating is presented, as well as a theoretical formalization for the effective index parallel with the normal to the surface. It is shown that a 2-D asymmetric binary grating on the surface of a dielectric substrate is analogous to a biaxial thin film. If the grating is symmetric, then the two effective indices perpendicular to the normal are equal, and the grating is analogous to a uniaxial thin film. Using these effective indices and the quarter-wave Tschebyscheff synthesis technique, we designed two- and three-level binary gratings to suppress reflections over a broad band. It is shown that for a substrate index of n(s) = 3.0 a three-level 2-D binary grating reduced reflections below 0.1% from 8 mu m to 12 mu m.
Journal of the Optical Society of America a-Optics Image Science and Vision
"Artificial Uniaxial And Biaxial Dielectrics With Use Of 2-Dimensional Subwavelength Binary Gratings" (1994). Faculty Bibliography 1990s. 1050.