Optical MEMS pressure sensor based on double ring resonator

Abstract

This work has focused on the design, simulation and analysis of an optical MEMS pressure sensor based on serially coupled double ring resonator (DRR) in a microcantilever for pressure sensing application. The sensor is basically structured on a microcantilever beam and built-in optical integrated ring resonator which is placed in one end of the beam to gain maximum stress on the resonator. A serially coupled DRR with different radii is investigated that, effective free spectral range (FSR) of the ring is dramatically enhanced due to the vernier effect between the two rings, and the cantilever beam is optimally designed to maximize the stress and also to reduce the size and weight of the device. As a result, when pressure is applied in a system, the beam will bend, which involves mechanical deformation of the ring resonator that induces a stress, which brings the refractive index change in the waveguide lead to change in the output spectrum shift providing the measure of pressure. The sensitivity as high as 3.4149pm/kPa has been achieved and it is capable of measuring within range of (0-30.469) MPa.