Temperature-insensitive fiber twist sensor based on elliptical-core few-mode fiber.

A highly sensitive fiber optics twist sensor is proposed and experimentally demonstrated using elliptical-core few-mode fiber (e-FMF). With the help of a fixed-phase plate for conversion from LP11 to LP01 mode, the twist angle can be linearly mapped to the spatial rotation of LP11 mode profile and consequently discriminated by monitoring the optical power variation at the standard single-mode fiber (SSMF) output. When the optical power at the e-FMF output is 10 mW, the twist angle within the range of ±39° can be successfully detected with a sensitivity of more than 20 μW/°. Meanwhile, the twist direction can be identified simultaneously. In particular, when the twist angle ranges from -12.5° to 20.1°, the sensitivity is higher than 100 μW/°. Both temperature-insensitive operation from 20°C to 150°C and e-FMF length insensitive operation are experimentally verified.

[1]  Wang Yiping,et al.  In fiber Bragg grating twist sensor based on analysis of polarization dependent loss. , 2013, Optics express.

[2]  J M Baptista,et al.  Simultaneous measurement of multiparameters using a Sagnac interferometer with polarization maintaining side-hole fiber. , 2008, Applied optics.

[3]  R. Ulrich,et al.  Polarization optics of twisted single-mode fibers. , 1979, Applied optics.

[4]  Songnian Fu,et al.  Design and fabrication of elliptical-core few-mode fiber for MIMO-less data transmission. , 2016, Optics letters.

[5]  Denis Donlagic,et al.  In-line, fiber-optic polarimetric twist/torsion sensor. , 2013, Optics letters.

[6]  Bo Liu,et al.  Highly sensitive twist sensor employing Sagnac interferometer based on PM-elliptical core fibers. , 2015, Optics express.

[7]  J.L. Santos,et al.  Fiber-Optic Interferometric Torsion Sensor Based on a Two-LP-Mode Operation in Birefringent Fiber , 2009, IEEE Photonics Technology Letters.

[8]  Y. Rao,et al.  Long period fibre grating torsion sensor measuring twist rate and determining twist direction simultaneously , 2004 .

[9]  Shuisheng Jian,et al.  Highly Sensitive Torsion Sensor Based on Sagnac Interferometer Using Side-Leakage Photonic Crystal Fiber , 2011, IEEE Photonics Technology Letters.

[10]  Hwa-Yaw Tam,et al.  Polarization-maintaining photonic-crystal-fiber-based all-optical polarimetric torsion sensor , 2010 .

[11]  Youngjoo Chung,et al.  Temperature-Insensitive Torsion Sensor With Enhanced Sensitivity by Use of a Highly Birefringent Photonic Crystal Fiber , 2010, IEEE Photonics Technology Letters.

[12]  Ezra Ip,et al.  Mode crosstalk matrix measurement of a 1  km elliptical core few-mode optical fiber. , 2016, Optics letters.

[13]  Eric J. Korevaar,et al.  Understanding the performance of free-space optics [Invited] , 2003 .