Abstract: A method for implementing folding M×N wavelength selective switch is provided. A one-dimensional single-mode fiber optic collimator array, a short-focus cylindrical mirror, a first long-focus cylindrical mirror, a retroreflector, a transmission phase diffraction grating, a second long-focus cylindrical mirror, a liquid crystal spatial light modulator, and a liquid crystal graphic loading control system are provided along beam transmission direction. The same set of optical elements is used for incident light and outgoing light by ingenious folding structure. The input port and output port of optical signal are consistent in spatial arrangement, thereby reducing space and improving port utilization. Based on composite liquid crystal chips, a working area of the liquid crystal spatial light modulator is doubled, and a quantity of accommodating ports is greatly increased. A quantity of M×N ports of the WSS can be increased greatly by the above structure and design.

Abstract: A method for implementing folding M×N wavelength selective switch is provided. A one-dimensional single-mode fiber optic collimator array, a short-focus cylindrical mirror, a first long-focus cylindrical mirror, a retroreflector, a transmission phase diffraction grating, a second long-focus cylindrical mirror, a liquid crystal spatial light modulator, and a liquid crystal graphic loading control system are provided along beam transmission direction. The same set of optical elements is used for incident light and outgoing light by ingenious folding structure. The input port and output port of optical signal are consistent in spatial arrangement, thereby reducing space and improving port utilization. Based on composite liquid crystal chips, a working area of the liquid crystal spatial light modulator is doubled, and a quantity of accommodating ports is greatly increased. A quantity of M×N ports of the WSS can be increased greatly by the above structure and design.