Mode Multiplexer/De-multiplexer In Few Mode Transmission System

With the rapid growth of network traffic demand in recent years,ultra-high speed and largecapacity optical transmission system is becoming more important than before.Mode multiplexer/de-multiplexer is a key component for multi-mode transmission.We put forward a novel multiplexer/de-multiplexer based on the currently existing different researches.The new multiplexer can simultaneously complete the mode modulation and multiplexing,this reduces the complexity of the whole system.Meanwhile,since the high order modes can be changed by loading different holograms,the mode used in the multiplexing system can be adjusted at any time.Besides,the diffraction efficiency of different diffraction orders can be equal after optimization,which is useful to long-distance transmission.This paper focuses on the design of blazed grating,we explain the principle of spatial light modulator.The phase modulation of the liner polarization mode and spatial light modulator is combined to realize the modulation of any liner polarization mode.The designed blazed grating can be optimized by using internal feedback system and genetic algorithm to ensure the diffraction efficiency of different diffraction orders is equal.