Design And Experimental Research On 4×4 MEMS Optical Switch Array

With the development of optical communication, all-optical cross-connections become possible. As the key component, optical switch has a greatmarket potential. MEMS based optical switches have the advantages of highperformance and low cost. In this dissertation, a research on a MEMS opticalswitch array with curved cantilever electrostatic actuator was donetheoretically and experimentally, and solutions for the key problems wereproposed. The main task includes: An optical model for MEMS optical switch array was founded, and themain optical parameters were designed through simulation. The efficiencies offiber-coupling in optical switches were calculated basing on the theory ofGaussian beam. The propagation rule through ball lens based on the ABCDmatrix was derived. The coupling efficiency of SMF (Single Mode Fiber) toSMF through two ball lenses was calculated. The contributing factors of thecoupling efficiency were analyzed. The radius of the ball lens and theposition of the tip of SMF were determined by numerical calculation and theinsert lose was optimized. The contributions of the different origins of InsertLoss in MEMS optical switches were given. And methods to reduce the losseswere introduced. The optical switch array with electrostatic actuator was designed. Theimportant processes of the optical switch were researched experimentally.The verticality and the surface roughness of the micro mirror were measured. Finite Element Method was used to analyze the stress distribution,resonance frequency and the deformation of the cantilever. Reduced-OrderModeling (ROM) was used to calculate the pull-in voltage of the curvedcantilever. ROM extracted the eigenmodes and their contribution factors. Thecoupled-physics domain was represented by a factored sum of mode shapes, so - II-英 文 摘 要the problem was simplified. Experiments have been done to measure thecurved height of the cantilever end, the first mode resonance frequency and thepull-in voltage. The failure modes of the optical switch were analyzed, which includes:stiction, mechanical fracture, delamination, fatigue and so on. The package ofthe optical switch array was designed.