Abstract

A curvature fiber optic sensor using a two-core fiber (TCF) is proposed and demonstrated. The TCF is designed to operate as a directional coupler with one core located exactly at the center of the fiber and the other off-axis, but close to the center of the fiber. This design allows straightforward splicing of the TCF to single mode fibers (SMF), and alignment of the off-axis core is not strictly required for optimum operation. The sensor is fabricated by simply splicing a 5 cm long section of TCF between two SMF sections, which provides a sinusoidal spectral response. When the fiber is bent, the coupling parameters are modified due to stress-optic and effective length effects, effectively blue-shifting the sinusoidal spectral response of the sensor and allowing for the measurement of curvature. The sensor exhibits linear response and a sensitivity of −137.87 nm/m−1 for curvature ranging from 0 to 0.27 m−1, making it suitable to measure small curvatures with high sensitivity.

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References

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  1. M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
  4. C. C. Ye, S. W. James, and R. P. Tatam, “Simultaneous temperature and bend sensing with long-period fiber gratings,” Opt. Lett.25(14), 1007–1009 (2000).
    [CrossRef] [PubMed]
  5. F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
    [CrossRef]
  6. H. Dobb, K. Kalli, and D. J. Webb, “Temperature-insensitive long period grating sensors in photonic crystal fibre,” Electron. Lett.40(11), 657–658 (2004).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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2012 (1)

2010 (1)

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

2009 (1)

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

2006 (1)

2004 (2)

H. Dobb, K. Kalli, and D. J. Webb, “Temperature-insensitive long period grating sensors in photonic crystal fibre,” Electron. Lett.40(11), 657–658 (2004).
[CrossRef]

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

2000 (3)

Y. Liu, L. Zhang, J. A. R. Williams, and I. Bennion, “Optical bend sensor based on measurement of resonance mode splitting of long-period fiber grating,” IEEE Photon. Technol. Lett.12(5), 531–533 (2000).
[CrossRef]

C. C. Ye, S. W. James, and R. P. Tatam, “Simultaneous temperature and bend sensing with long-period fiber gratings,” Opt. Lett.25(14), 1007–1009 (2000).
[CrossRef] [PubMed]

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

1983 (1)

A. J. Barlow and D. N. Payne, “The stress-optic effect in optical fibers,” IEEE J. Quantum Electron.19(5), 834–839 (1983).
[CrossRef]

1981 (3)

1976 (1)

H. Kogelnik and R. V. Schmidt, “Switched directional couplers with alternating Δβ,” IEEE J. Quantum Electron.12(7), 396–401 (1976).
[CrossRef]

1972 (1)

Allsop, T.

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

Baptista, J. M.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Barlow, A. J.

A. J. Barlow and D. N. Payne, “The stress-optic effect in optical fibers,” IEEE J. Quantum Electron.19(5), 834–839 (1983).
[CrossRef]

Bennion, I.

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Y. Liu, L. Zhang, J. A. R. Williams, and I. Bennion, “Optical bend sensor based on measurement of resonance mode splitting of long-period fiber grating,” IEEE Photon. Technol. Lett.12(5), 531–533 (2000).
[CrossRef]

Blanchard, P. M.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Burnett, J. G.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Chen, N.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Chen, Z.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Dobb, H.

H. Dobb, K. Kalli, and D. J. Webb, “Temperature-insensitive long period grating sensors in photonic crystal fibre,” Electron. Lett.40(11), 657–658 (2004).
[CrossRef]

Dong, X.

Earthgrowl-Gould, T.

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

Edahiro, T.

K. Okamoto, T. Hosaka, and T. Edahiro, “Stress analysis of optical fibers by a finite element method,” IEEE J. Quantum Electron.17(10), 2123–2129 (1981).
[CrossRef]

El-Bayoumi, O. H.

Frazão, O.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Gander, M. J.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Gillooly, A.

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

Greenaway, A. H.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Han, Y. G.

Hosaka, T.

K. Okamoto, T. Hosaka, and T. Edahiro, “Stress analysis of optical fibers by a finite element method,” IEEE J. Quantum Electron.17(10), 2123–2129 (1981).
[CrossRef]

James, S. W.

Jones, J. D. C.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Kalli, K.

H. Dobb, K. Kalli, and D. J. Webb, “Temperature-insensitive long period grating sensors in photonic crystal fibre,” Electron. Lett.40(11), 657–658 (2004).
[CrossRef]

Kobelke, J.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Kogelnik, H.

H. Kogelnik and R. V. Schmidt, “Switched directional couplers with alternating Δβ,” IEEE J. Quantum Electron.12(7), 396–401 (1976).
[CrossRef]

Lagakos, N.

Lee, J. H.

Lee, S. B.

Liang, W.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Liu, Y.

Y. Liu, L. Zhang, J. A. R. Williams, and I. Bennion, “Optical bend sensor based on measurement of resonance mode splitting of long-period fiber grating,” IEEE Photon. Technol. Lett.12(5), 531–533 (2000).
[CrossRef]

MacPherson, W. N.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Margulis, W.

McBride, R.

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Mezentsev, V.

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

Mohr, R.

Murakami, Y.

Neal, R.

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

Okamoto, K.

K. Okamoto, T. Hosaka, and T. Edahiro, “Stress analysis of optical fibers by a finite element method,” IEEE J. Quantum Electron.17(10), 2123–2129 (1981).
[CrossRef]

Pang, F.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Payne, D. N.

A. J. Barlow and D. N. Payne, “The stress-optic effect in optical fibers,” IEEE J. Quantum Electron.19(5), 834–839 (1983).
[CrossRef]

Richmond, P.

Rugeland, P.

Santos, J. L.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Schmidt, R. V.

H. Kogelnik and R. V. Schmidt, “Switched directional couplers with alternating Δβ,” IEEE J. Quantum Electron.12(7), 396–401 (1976).
[CrossRef]

Schuster, K.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Silva, S. F. O.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Snyder, A. W.

Sudo, S.

Tatam, R. P.

Viegas, J.

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Wang, T.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Webb, D. J.

H. Dobb, K. Kalli, and D. J. Webb, “Temperature-insensitive long period grating sensors in photonic crystal fibre,” Electron. Lett.40(11), 657–658 (2004).
[CrossRef]

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

Williams, J. A. R.

Y. Liu, L. Zhang, J. A. R. Williams, and I. Bennion, “Optical bend sensor based on measurement of resonance mode splitting of long-period fiber grating,” IEEE Photon. Technol. Lett.12(5), 531–533 (2000).
[CrossRef]

Xiang, W.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Ye, C. C.

Zeng, X.

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

Zhang, L.

Y. Liu, L. Zhang, J. A. R. Williams, and I. Bennion, “Optical bend sensor based on measurement of resonance mode splitting of long-period fiber grating,” IEEE Photon. Technol. Lett.12(5), 531–533 (2000).
[CrossRef]

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

Appl. Opt. (3)

Electron. Lett. (2)

M. J. Gander, W. N. MacPherson, R. McBride, J. D. C. Jones, L. Zhang, I. Bennion, P. M. Blanchard, J. G. Burnett, and A. H. Greenaway, “Bend measurement using Bragg gratings in multicore fibre,” Electron. Lett.36(2), 120–121 (2000).
[CrossRef]

H. Dobb, K. Kalli, and D. J. Webb, “Temperature-insensitive long period grating sensors in photonic crystal fibre,” Electron. Lett.40(11), 657–658 (2004).
[CrossRef]

IEEE J. Quantum Electron. (3)

K. Okamoto, T. Hosaka, and T. Edahiro, “Stress analysis of optical fibers by a finite element method,” IEEE J. Quantum Electron.17(10), 2123–2129 (1981).
[CrossRef]

A. J. Barlow and D. N. Payne, “The stress-optic effect in optical fibers,” IEEE J. Quantum Electron.19(5), 834–839 (1983).
[CrossRef]

H. Kogelnik and R. V. Schmidt, “Switched directional couplers with alternating Δβ,” IEEE J. Quantum Electron.12(7), 396–401 (1976).
[CrossRef]

IEEE Photon. Technol. Lett. (3)

F. Pang, W. Liang, W. Xiang, N. Chen, X. Zeng, Z. Chen, and T. Wang, “Temperature-insensitive bending sensor based on cladding-mode resonance of special optical fiber,” IEEE Photon. Technol. Lett.21(2), 76–78 (2009).
[CrossRef]

O. Frazão, S. F. O. Silva, J. Viegas, J. M. Baptista, J. L. Santos, J. Kobelke, and K. Schuster, “All Fiber Mach–Zehnder Interferometer Based on Suspended Twin-Core Fiber,” IEEE Photon. Technol. Lett.22(17), 1300–1302 (2010).
[CrossRef]

Y. Liu, L. Zhang, J. A. R. Williams, and I. Bennion, “Optical bend sensor based on measurement of resonance mode splitting of long-period fiber grating,” IEEE Photon. Technol. Lett.12(5), 531–533 (2000).
[CrossRef]

IEEE Trans. Instrum. Meas. (1)

T. Allsop, A. Gillooly, V. Mezentsev, T. Earthgrowl-Gould, R. Neal, D. J. Webb, and I. Bennion, “Bending and orientational characteristics of long period gratings written in D-shaped optical fiber,” IEEE Trans. Instrum. Meas.53(1), 130–135 (2004).
[CrossRef]

J. Opt. Soc. Am. (1)

Opt. Lett. (2)

Other (3)

K. Okamoto, Fundamentals of Optical Waveguides, 2nd Ed. (Academic Press - Elsevier, 2006), Chap. 1.

E. P. Popov, Mechanics of Materials, 2nd Ed. (Prentice Hall, 1976), Chap. 9.

S. P. Timoshenko, Strength of Materials. Part 1, 2nd Ed. (D. Van Nostrand Company, 1940), Chap. 8.

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Figures (6)

Fig. 1
Fig. 1

(a) Cross-section of the Two-Core Fiber. (b) Spectral response of the TCF in the spectral window from 1465 nm to 1665 nm.

Fig. 2
Fig. 2

Spectral behavior of the coupling coefficient.

Fig. 3
Fig. 3

Spectral response of the TCF due to (a) stress-optic effect, (b) changes in the effective length, and (c) absolute wavelength shift as a function of the applied curvature.

Fig. 4
Fig. 4

Experimental characterization setup of the TCF curvature sensor.

Fig. 5
Fig. 5

(a) Spectral response of the TCF-based curvature Sensor. (b) Absolute wavelength shift with respect to curvatures: comparison between experimental and theoretical results.

Fig. 6
Fig. 6

(a) Absolute wavelength shift of the sensor as a function of the applied curvature for different separations between the cores. (b) Temperature response of the curvature sensor.

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

κ= 2Δ a U 2 K 0 ( Ws a ) V 3 [ K 1 ( W ) ] 2
σ= P A = ( 2E I z d e L 2 ) A
Δn= C stropt σ
P Trans ( z )= cos 2 ( κ 2 + δ 2 z )+ δ 2 κ 2 + δ 2 sin 2 ( κ 2 + δ 2 z )
P Trans ( λ,C )= cos 2 [ κ( λ,C ) L 0 ]

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