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Updated: May 18, 2026
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Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
Angular bandpass filters based on dielectric resonant waveguide gratings
Stefan Steiner1, Stefanie Kroker, Thomas Käsebier
1Institut für Angewandte Physik, Abbe-Center of Photonics, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, Jena 07743, Germany. stefan.steiner@uni-jena.de
Optics Express
|October 6, 2012
Summary
Researchers developed novel resonant waveguide gratings (RWGs) for direction-selective optical filters. These silicon-based filters achieve high transmission at specific angles, offering tunable angular selectivity for advanced optical applications.
Area of Science:
- Optics and Photonics
- Materials Science
- Nanotechnology
Background:
- Resonant waveguide gratings (RWGs) offer unique optical properties.
- Direction-selective filters are crucial for various optical systems.
- Silicon's high refractive index is advantageous for optical element fabrication.
Purpose of the Study:
- To introduce a novel concept for transmissive optical elements using RWGs.
- To demonstrate the realization of direction-selective filters.
- To explore the tunability of transmission angles and bandwidths.
Main Methods:
- Utilizing silicon for its high refractive index and semiconductor fabrication compatibility.
- Designing RWGs to combine broadband reflectivity at normal incidence with high transmission efficiency at specific angles.
- Adjusting grating parameters to control transmission characteristics.
Main Results:
- Achieved high transmission efficiency up to 63% at an incidence angle of 45 degrees.
- Demonstrated a narrow angular width of 20 degrees (full width at half maximum).
- Showcased the feasibility of tuning transmission angles and angular widths by adjusting grating parameters.
Conclusions:
- RWGs provide a viable platform for creating efficient, direction-selective transmissive optical filters.
- The silicon-based approach is compatible with established semiconductor manufacturing processes.
- Tunable angular selectivity makes these filters suitable for diverse optical applications.
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