Recent Development in the Distributed Fiber Optic Acoustic and Ultrasonic Detection

Distributed acoustic sensors provide a powerful instrumentation for ultrasound testing to identify the internal crack and deformation with the location for assessing structural conditions and predicting the potential structural failure. This paper provides a tutorial review of the milestones leading to the development of the distributed acoustic sensor based on Rayleigh back scattering. It offers discussion on basic principles, optical configurations and system design requirement, various detection schemes, performance limitations and applications for the maximum measurable frequency, minimum detectable strain and highest spatial resolution. A final comment on the prospects of the further developments is presented.