CWDM planar concave grating multiplexer/demultiplexer and application in ROADM

We report a SOI based 1×4 coarse wavelength-division-multiplexer (CWDM) planar concave grating multiplexer/demultiplexer and applications in re-configuration optical add/drop multiplexer (ROADM) system. For design, we employed recursion numerical method to build a low aberration, non-circle grating circle model of concave grating. For experiment, CMOS compatible silicon planar integration technology is used for device fabrication. The concave grating multiplexer wavelengths are well fitted within ITU-T standard. Two CWDMs and four wide-band optical switches composited to prototype of ROADM have been fabricated, too. The ROADM function performance is presented.