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The Fabry-Perot interferometer (FP) can be used as a kind of filter for obtaining spectral information of targets in several wavelength ranges such as in the visible or infrared regions. Micro-electro-mechanical systems (MEMS) are generally micro-structures that integrate micro-sensors for converting incident microbeams into arrayed electronic signals and micro-actuators. The MEMS-FP filter constructed by combining the MEMS and FP functions, can be further integrated into a chip-level imaging spectrometer to achieve spectral imaging operation. In our design, the MEMS-FP filter is also mounted a liquid-crystal microlens array with a high filling-factor. The key micro-bridges of each MEMS-FP unit are modeled and simulated in this paper. We have designed two types of supporting structures and simulated them with the simulation software COMSOL Multiphysics 5.2. The key factors include tuning range, filling-factor, and parallelism of the bridges. After calculating and analyzing, we found that the tuning range can be optimized by changing the thickness of the micro-bridge and the arm width of the cantilever beam. The filling-factor is already increased by geometry design. The parallelism of the bridge in the two micro-structures differs greatly, which is related to the shape of the bridge itself. According to the simulations, a tuning range of 160 nm has been achieved in the visible and near-infrared wavelength range, with a maximum filling-factor of more than ~80%.
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