Open AccessAngular bandpass filters based on dielectric resonant waveguide gratings
Author(s) -
Stefan H. Steiner,
Stefanie Kroker,
Thomas Käsebier,
ErnstBernhard Kley,
Andreas Tünnermann
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.022555
Subject(s) - optics , materials science , refractive index , band pass filter , broadband , grating , optical filter , diffraction grating , dielectric , fabrication , transmission (telecommunications) , angle of incidence (optics) , guided mode resonance , waveguide , total internal reflection , optoelectronics , diffraction efficiency , physics , telecommunications , medicine , alternative medicine , pathology , computer science
We report on a novel concept for transmissive optical elements based on resonant waveguide gratings (RWGs), which enables the realization of direction selective filters. Hereby, the broadband reflectivity of an RWG for nearly normal incidence angles is combined with high diffractive efficiency in transmission for a specific angle of incidence. Silicon is used as material with high refractive index and good compatibility with semiconductor fabrication. By adjusting the grating parameters different transmission angles and angular widths of the transmission range are feasible. First experimental results of the introduced filters provide a high transmission up to 63% at an incidence angle of 45° with a full width at half maximum of 20°.