access icon free FBG laser sensor with PS

Owing to unstable multi-wavelength lasing, robust measurement is difficult with a fibre Bragg grating (FBG) laser sensor system that uses FBGs as laser cavity mirrors as well as sensors. A stabilising technique is essential for proper data acquisition. Here, it is demonstrated that polarisation scrambling (PS) stabilises the output of laser sensor system in combination with a spectrometer demodulation. The state of polarisation (SOP) of a fibre-optic laser cavity is changed by a 1 MHz PS. A 5 kHz spectrometer traces the distribution of output laser wavelengths. The rapid changes in SOP make all the FBG wavelengths lase as long as necessary to determine the Bragg wavelength shifts in the sampling windows of a photo-diode array. A laser sensor system with eight FBG sensors is used to demonstrate robust measurement and data collection under environmental perturbations.

Inspec keywords: fibre optic sensors; Bragg gratings; photodiodes; optical fibre polarisation; laser stability; laser cavity resonators; data acquisition; demodulation; laser mirrors

Other keywords: FBG wavelengths; output laser wavelengths; data acquisition; state of polarisation; spectrometer demodulation; fibre Bragg grating laser sensor system; polarisation scrambling; laser cavity mirrors; frequency 5.0 kHz; FBG sensors; unstable multiwavelength lasing; fibre-optic laser cavity; FBG laser sensor; stabilising technique; Bragg wavelength shifts

Subjects: Fibre lasers and amplifiers; Other fibre optical properties; Laser resonators and cavities; Fibre lasers and amplifiers; Optical interferometry; Spatial variables measurement; Gratings, echelles; Laser accessories and instrumentation; Optical spectroscopy and spectrometers; Spatial variables measurement; Fibre optic sensors; Fibre optic sensors; fibre gyros; Laser resonators and cavities; Optical lenses and mirrors; Other fibre optical devices and techniques

References

    1. 1)
      • 1. Werneck, M.M.M., Allil, R.C., de Nazaré, F.V.: ‘Fibre Bragg gratings’ (SPIE Press, Bellingham, Washington, D.C., USA, 2017).
    2. 2)
    3. 3)
    4. 4)
      • 3. Kim, H., Kim, D., Song, M.: ‘Stabilization of fiber Bragg grating laser sensor with polarization scrambling’. Proc. SPIE, Santander, Spain, June 2014, vol. 9157, p. 91579Z, doi: 10.1117/12.2059480.
    5. 5)
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