Abstract:We propose and demonstrate a tunable filter by using full conical mounting. The designed 1D resonant waveguide grating presents a tunable single reflection peak. The peak reflectance can theoretically reach 100%. The resonant wavelength can be tuned from 642.5 nm to 484.6 nm by changing incident angle. The reflection peak is generated by the resonance between 1st-order diffracted wave and fundamental transverse electric (TE) guided mode. This feature is achieved by optimizing the grating thickness to support the TE guided mode and to suppress the transverse magnetic (TM) guided mode. The same concept can be applied to tunable filters with high dynamic range by increasing the thickness and period of grating in equal proportion.