Tunable polymer optical add/drop filter for multiwavelength networks

We present a polymer optical add/drop filter with a channel cross-talk of -18.5 dB, a free spectral range of 12.8 nm and a channel spacing of 400 GHz (4 channels) as well as a tunable optical filter with a free spectral range of 50 nm. Both filter designs are based on a synthesis which provides the minimum number of filter stages for a given channel crosstalk and number of channels. Wavelength tunability over the entire free-spectral range (FSR) is demonstrated with applied heating powers of 500 mW. For the narrow bandwidth filter we used a fluorinated high temperature stable polymer as the waveguiding material, which has proven to exhibit losses as low as 0.25 dB/cm at a wavelength of 1.55 μm.