Quasi-static and dynamic strain sensing is performed by means of a fibre Bragg-grating resonator based on an optical-frequency-comb stabilised laser. The comb synthesizer, centred around 1560 nm, is a fs-pulsed fibre laser, which is phase-locked to an ultra-stable quartz oscillator, serving as an optical reference to minimise laser-frequency and phase noise both in the long and short-term operation. Detection limits in the order of a few peRMS/√Hz, in the Hz and sub-Hz range, are demonstrated, while a sub- pe sensitivity is expected at higher frequencies in the acoustic range.
