TI : LINBO3 ACOUSTO-OPTIC TUNABLE FILTER (AOTF)

We have developed the following new elements for an AOTF: an intersecting waveguide PBS which has a high extinction ratio, low loss, and wavelength independent characteristics; a film-loaded SAW guide (SAWG) which has a strong confinement, excellent filter characteristics, and provides a high design flexibility; and a 0-gap directional coupler type reflector which enables high-performance waveguide integration. These elements were combined to construct an AOTF consisting of five film-loaded SAWGs. The through and drop lights in this AOTF are filtered by three stages of the new SAWG. The 3 dB bandwidth and extinction ratio are 0.37 nm and less than -27 dB, respectively. An optical ADM system that incorporated the new AOTF has demonstrated 10 Gb/s × 32-channel transmission with a 0.8 nm wavelength spacing.