Optical Design of an LCoS-based 1×10 WSS with High Coupling Efficiency and Compact Light Paths

In the field of communication, liquid crystal on silicon (LCoS) wavelength selection switches (WSS) systems are of great significance but the lack of research on its optical path design makes it challenging to realize high-port-count and perfect performance with a compact structure. In this paper, the optical path design method of a compact LCoS-based 1×10 WSS system working in C-band (1529nm~1568nm) is proposed, where there exists 1 input port and 10 output ports in the same array. The distribution of optical power in the two directions is taken into account independently, boosting system compactness, lowering assembly and manufacturing costs. Finally, a high fiber-to-fiber coupling efficiency ranging from 95.07% to 99.18% is achieved, corresponding to ultra-low simulation loss of less than 0.22dB. Furthermore, a brief tolerance analysis to demonstrate the instrumentation feasibility is also conducted. Our work is pioneering in providing a more straightforward evaluation method and a more workable solution for the optical design of WSS systems.