Ruggedized MEMS-VCSELwith high speed data acquisition for Fiber Optic Sensing System

This work will develop and validate a new wavelength swept laser for fiber optic sensing systems (FOSS). Existing FOSS technology usesnbsp;external cavity tunable lasers, whichnbsp;are assembled from discrete components with precision intracavitynbsp;laser alignments. This creates cost and complexity, inhibits volume scaling,nbsp;and inhibits ruggedization.nbsp;nbsp;These factors havenbsp;in turn inhibited widespread commercial adoption of FOSS in avionics applications and precluded embedding this technology into commercial flight vehicles for continuous in-flight structural health monitoring.nbsp;nbsp;Praevium will endeavor to solve these problems by building on its prior work done in developing micro-electromechanical systems tunable vertical cavity surface emitting lasers (MEMS-VCSELs) for swept source optical coherence tomography (SSOCT). Although FOSS employs optical frequency domain reflectometry (OFDR), which is similar to SSOCT, thenbsp;much longer interferometer delays and much lower wavelength sweep rates employed in FOSS require the effects of Brownian motion on the MEMS actuatornbsp;to be mitigated.nbsp;In this work, Praevium Research will minimize the effects of Brownian motion through re-design of the MEMS actuator structure. Additionally, Praeviumnbsp;will develop a low weight and power ruggedized butterfly package based on newly emerging electrically pumped MEMS-VCSELs, eliminating costly and bulky components such as the pump laser, isolator, and wavelength division multiplexer needed in commercial optically pumped devices. Praevium will work with subcontractor Sensuron, who has expertise in FOSS to evaluate the newly developed laser. Sensuron will evaluate the Praevium MEMS-VCSEL in various interferometer configurations, and develop high speed data acquisition and computation to integrate the new laser into a fiber bragg grating based sensor measurement. Results will be compared with existing laser sources.nbsp;