MEMS Tunable Optical Filter Using Auto-Cloned Photonic Crystal

This paper proposes a novel MEMS tunable optical filter (TOF) using an auto-cloned photonic crystal (PhC). The auto-cloning method has great gains to fabricate multi-dimensional PhCs in productivity, flexibility and robustness. A two-dimensional PhC was fabricated by stacking Nb2O5and SiO2layers alternately keeping nano-scale periodic corrugations (190nm in pitch) formed on a substrate. This PhC was designed for splitting an incident light into the TM and TE modes at 500nm. Photonic band-gaps were changed by rotating the PhC and the transmittance of the TE mode was changed drastically at 420nm. The PhC was attached on the MEMS device (Eco Scan: Japan Signal) to control its angle of incidence. A resonance frequency of the MEMS structure was 183Hz and that rotation angle reached up to 40 degree. Switching characteristics of our MEMS-TOF were confirmed and its availability was demonstrated.