Micro-opto-electro-mechanical systems accelerometer based on the Talbot effect of double-layer diffraction gratings

Abstract

In this paper, we present the design, fabrication, and test of a micro-opto-electro-mechanical systems (MOEMS) accelerometer based on the Talbot effect of double-layer diffraction gratings. The detection of acceleration is realized by using the highly sensitive displacement characteristic of Talbot imaging of near-field diffraction with double-layer gratings. For the purpose of obtaining optimal contrast of the optical interferometric detection, the parameters of the gratings are optimized by the finite-difference time-domain (FDTD) simulation. The experimental results indicate that this MOEMS accelerometer with the proposed design can achieve a resolution of 246 µg, sensitivity of 6.1 V/g, and bias stability of 0.02 mg. The proposed accelerometer can be operated at higher accelerations ( ∼ 80 g ), which shows significant potential for being used in applications that require detection of strong and fast vibrations, especially in vibration sensing of vehicles and geophysical seismic sensing in real time.