Single- and multipoint fiber-laser sensors

The operation of single- and multipoint active fiber sensors for both strain and temperature measurements is reported. An active fiber source consists of a pair of wavelength-matched Bragg gratings formed in a rare earth doped fibre, and when, optically pumped, lase in a narrow bandwidth around the Bragg wavelength. The primary advantage of an active sensor over a passive sensor is a significant increase in signal-to-noise ratio.<
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