论文信息 - Study on thermomechanical reliability of a tunable light modulator

Study on thermomechanical reliability of a tunable light modulator

Abstract A unique light modulator based on surface modulation of thin films is being developed for applications in fiber optical telecommunication. By controlling the surface deformation of the gel layer with electrical potentials, the light modulator acts as a tunable diffraction grating and the light intensity can be varied continuously within a few microseconds. In order to investigate possible thermomechanical failure modes and supply preliminary guidelines for design, a three-dimensional finite element analysis was conducted on the modulator assembly. The numerical results revealed that the maximum peel stress is developing along short edges of the adhesive layer and interfacial delamination may initiate around this site during the thermal cycling. The subsequent thermal cycling test qualitatively supported the simulated results. Additionally, the consequences of changing a number of geometry and material parameters were evaluated based on modeling efforts, and design recommendations have been made.

Shiming Li | Johan Liu | Helge Kristiansen | Zhimin Mo | Morten Eliassen

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