AWG-Based Tunable Optical Dispersion Compensator With Multiple Lens Structure

We propose an arrayed-waveguide grating (AWG)-based tunable optical dispersion compensator (TODC) that uses a multiple lens structure with two lens materials. The lenses are realized by filling lens-shaped trenches in a slab waveguide with optical resins. The thermooptic effect provided by the lens materials realizes the desired dispersion tuning function. The multiple lens structure enables us to design the center dispersion and the dispersion tuning range independently. We fabricate a TODC based on a 10-ch, 10-GHz spacing AWG that uses resins with refractive indexes of 1.393 and 1.510. Its dispersion range is 0 to + 125 ps/nm. We also perform a transmission experiment using a 12.5 Gbps RZ-OOK signal. The power penalty at the bit error rate of 10^-9 is less than 3 dB; and error-free transmission is confirmed after dispersion compensation.