Optimal Design And Simulation Of Wavelength Selective Switch Optical System

Wavelength selection switch(WSS)is the core optical component in current reconfigurable optical add/drop multiplexer(ROADM)that is a research hotspotin the field of optical communication technology in recent years.Because of thesignificant advantages of liquid crystal on silicon(LCoS)in all-optical signal processing,LCoS based WSS have gradually become the important equipment,and have broad and important applications prospects in intelligent elastic optical networks,ultra-fast optical,multi-dimensional multiplexing/demultiplexing technologies for optical signals.On the other hand,it is also very important in the application prospects and actual research value field of ecological protection and agricultural production that WSS can be widely used for the accurate identification of different plants according to surfaces structure of plant leaf for different wavelengths of specular and diffuse reflections.However,the current wavelength selective switching technology is limited by the information processing capability of the LCoS chip and the complexity of the WSS optical system.The port number and wavelength resolution cannot meet the application and development requirements of WSS in the field of optical communication and ecological technology that is urgently needed further in-depth research.In this paper,the model of wavelength selective switch based 2f opticalsystem has been built by using ZEMAX optical simulation design software.According to optimize the Fourier lens imaging system and cylindrical mirror imaging system inside the optical system,the imaging quality of the whole optical system has been significantly improved,and the experimental research of wavelength selective switch has been carried out based on the simulation optimization results.The main work done by the thesis is as follows:(1)The important application prospects and research value of wavelength selective switches in the fields of optical communication,plant identification and agricultural production were elaborated.A possible technical solution for applying wavelength selective switch to plant identification is proposed,and a comprehensive analysis and discussion of its main core optical components is carried out.(2)The ZEMAX optical design software was used to simulate and optimize the overall optical system of the wavelength selective switch.After the optimized Fourier optical system,a phase diffraction grating,a cylindrical mirror,and the LCoS is simulated by a mirror to obtain an entire wavelength selective switching optical system.After multiple optimizations of the evaluation function,a finer single-wavelength spot on the LCoS was obtained.The deflection angle of the liquid crystal cell pixel is simulated by setting multiple-configuration on the mirror,so that the light beam returns through the reflection path of the LCoS,and was coupled into a multiport fiber coupling microlens array,thereby realizing ZEMAX simulation of the WSS integral optical system.(3)A wavelength selective switch experimental system based on LCoS was built to realize a WSS with 65 port numbers based on the simulation optimization of the WSS and its core optical components.To further improve the spectral resolution of this WSS,the optical spot on LCoS is narrowed to a range of 32?m by optimizing the cylindrical lens,so that the minimum filtering bandwidth of the entire c-band can reach 8GHz.The above research results of the thesis have important reference value and practical significance for promoting the intelligence of optical networks and the application in the fields of ecological protection and agricultural production.