Compact Wavelength Selective Switch Using a Bragg Reflector Waveguide Array With Ultra-Large Number (>100) of Output Ports

A wavelength selective switch (WSS) is proposed based on a Bragg reflector waveguide array, which has a footprint of only 2 × 6 mm². We demonstrated arbitrary switching among 182 output ports by using a liquid crystal on silicon as a switching engine. The proposed WSS module length is only 10 cm, taking an advantage of the large angular dispersion in the Bragg reflector waveguide. Wavelength selective switching of 60 channels is carried out, exhibiting the device´s excellent capability in providing ultra-large number of port count and wavelength channel operations at the same time. The crosstalk between adjacent ports are below -20 dB by a suitable alignment, which can be further improved by optimizing the module optics and alignments. The flexible lithography defined waveguide array design also reveals versatile potentials in integrating with other functional components.