A two-dimensional dual-wavelength routing network with 1-to-10 cascaded fanouts

A two-dimensional (2-D) wavelength-division demultiplexing device [WD(D)M] is demonstrated to separate and to distribute optical signals of different wavelengths by use of substrate-guided wave optical interconnects. In our experiment, two stacked input holographic gratings are fabricated to steer two optical wavelengths into two different routing directions and to zigzag within a waveguiding substrate. Input coupling efficiencies of 70% and 76% are experimentally confirmed at the input wavelengths of 780 and 790 nm, respectively. Two arrays of 1-to-10 cascaded output holographic grating couplers are employed to couple out the optical signals with surface-normal fanouts. The crosstalk is measured to be <-30 dB. The fanout energy fluctuation is within /spl plusmn/10% for each wavelength.