MOEMS tunable optical filter based on photonic crystals

1-D photonic crystals with defects such as (L1H1)(LCH2)-L-m(L2H2)(n) are investigated. The bandgap edge transmission peak is narrowed when the couple layer L-C and the cover layer H-2(L2H2)(n) are added to the photonic crystal (L1H1)(m). Three different structures are studied. Structure A is not suitable for the tunable filter, which has two discrete tuning regions. Structures B and C provide good optical tuning methods: large dynamic range (> 150nm), narrow bandwidth [full-width at half maximum (FWHM) is about 2 nm], and good tuning linearity. These structures can be easily fabricated by the surface micromachined technique. (c) 2005 Society of Photo-Optical Instrumentation Engineers.