A Proposal for an Optical MEMS Accelerometer With High Sensitivity Based on Wavelength Modulation System

Abstract

In our work, an optical MEMS accelerometer based on wavelength modulation is proposed, using a double nanoscale distributed Bragg reflector (nano-DBR) structure. In view of its specific structure, this proposed accelerometer consists of a mechanical structure and an optical system, which have been studied by finite element analysis (FEA) and rigorous coupled wave analysis (RCWA) respectively. By comparing the proposed accelerometer with other previously reported works, this accelerometer has high performance in terms of sensitivity, resolution and good linearity in the whole modulation range. The effective simulation results have demonstrated as follows: a resonance frequency of 562.85 Hz, a wavelength modulation range of 1.1 to 2.63 μm, a measurement range of ±1.56 g, a mechanical sensitivity of 781.64 nm/g, an optical system sensitivity of 1.23, an accelerometer sensitivity of 964.35 nm/g, a resolution of 1.037 μg, and low cross-sensitivity. According to such functional characters, the proposed accelerometer can be used for improvements in MEMS inertial navigation devices.