1 December 2017 Fibre optic gyroscope with single-mode fibre and loop-back phase shift compensation
Author Affiliations +
Proceedings Volume 10603, Photonics, Devices, and Systems VII; 1060309 (2017) https://doi.org/10.1117/12.2292298
Event: Photonics Prague 2017, 2017, Prague, Czech Republic
An all-fibre optical sensor of an angular velocity (fibre-optic gyroscope) based on the Sagnac interferometer and using a loop-back phase shift compensation is presented. The sensing loop consists of 760 metres of an ordinary single-mode fibre, which makes this setup cost-effective. To ensure principles of beams reciprocity, randomly induced changes of polarization in the fibre are reduced by using an unpolarized light. This is achieved by a fibre Lyot depolarizer and a super fluorescent fibre source consisting of an erbium-doped fibre pumped by a laser diode. Unlike common approaches to the unpolarized fibre-optic gyroscope with a single-mode fibre, whose output is naturally nonlinear, we use a loop-back compensation of a rotation-induced phase shift to achieve a linear response. In most cases, this technique requires fast electro-optical modulator, which is compatible only with an expensive polarization-maintaining fibre. We use a novel loop-back modulation scheme utilizing only harmonic signals and thus compatible with a piezoelectric fibre stretcher, which can be used with any kind of optical fibre. As result of the closed-loop operation, the range of the gyroscope's linearity is greatly increased and a sensitivity to source power changes is suppressed. We describe the gyroscope setup with proposed modulation method and provide a comparison to the common open-loop setup.
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michal Skalský, Michal Skalský, Zdeněk Havránek, Zdeněk Havránek, Jiří Fialka, Jiří Fialka, } "Fibre optic gyroscope with single-mode fibre and loop-back phase shift compensation", Proc. SPIE 10603, Photonics, Devices, and Systems VII, 1060309 (1 December 2017); doi: 10.1117/12.2292298; https://doi.org/10.1117/12.2292298


Back to Top