Abstract

We present modeling, design, fabrication and characterization of a new type of all-optical frequency modulated MEMS force sensor based on a mechanically amplified double clamped waveguide beam structure with integrated Bragg grating. The sensor is ideally suited for force measurements in harsh environments and for remote and distributed sensing and has a measured sensitivity of −14 nm/N, which is several times higher than what is obtained in conventional fiber Bragg grating force sensors.

©2011 Optical Society of America

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References

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  • Publication
  1. Z. Zhou and J. Ou, “Techniques of temperature compensation for FBG strain sensors used in long-term structural monitoring,” Proc. SPIE, 167–172 (2005).
    [Crossref]
  2. H. Fu, J. Fu, and X. Qiao, “High sensitivity fiber Bragg grating pressure difference sensor,” Chin. Opt. Lett. 2, 621–623 (2004).
  3. J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
    [Crossref]
  4. D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
    [Crossref]
  5. X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
    [Crossref]
  6. Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
    [Crossref]
  7. Y. I. Rzhavin, “Fiber-optic polarization pressure sensor,” Meas. Tech. 45, 738–741 (2002).
    [Crossref]
  8. E. Bonnotte, C. Gorecki, H. Toshiyoshi, H. Kawakatsu, H. Fujita, K. Worhoff, and K. Hashimoto, “Guided-wave acoustooptic interaction with phase modulation in a ZnO thin-film transducer on an Si-based integrated Mach-Zehnder interferometer,” J. Lightwave Technol. 17, 35–42 (1999).
    [Crossref]
  9. D. Graham-Rowe, “Sensors take the strain,” Nat. Photonics 1, 307–309 (2007).
    [Crossref]
  10. W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
    [Crossref]
  11. L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
    [Crossref]
  12. W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
    [Crossref]
  13. L. Eldada, “Polymer integrated optics: promise vs. practicality,” Org. Photon. Mater. Dev. IV 4642, 11–22 (2002).

2010 (1)

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

2009 (1)

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

2007 (2)

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

D. Graham-Rowe, “Sensors take the strain,” Nat. Photonics 1, 307–309 (2007).
[Crossref]

2005 (1)

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

2004 (3)

H. Fu, J. Fu, and X. Qiao, “High sensitivity fiber Bragg grating pressure difference sensor,” Chin. Opt. Lett. 2, 621–623 (2004).

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

2002 (2)

Y. I. Rzhavin, “Fiber-optic polarization pressure sensor,” Meas. Tech. 45, 738–741 (2002).
[Crossref]

L. Eldada, “Polymer integrated optics: promise vs. practicality,” Org. Photon. Mater. Dev. IV 4642, 11–22 (2002).

2001 (1)

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

1999 (1)

Barber, J. P.

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

Berganzo, J.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Bonnotte, E.

Chen, J.

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

Chicharo, J.

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

Dai, Y.

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Deamer, D. W.

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

Deng, F.

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Deng, Y.-long

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

Dominguez, C.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Dong, X.

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

Eldada, L.

L. Eldada, “Polymer integrated optics: promise vs. practicality,” Org. Photon. Mater. Dev. IV 4642, 11–22 (2002).

Esteve, J.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Fen, Z.

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Fu, H.

Fu, J.

Fujita, H.

Garcia, J.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Gorecki, C.

Graham-Rowe, D.

D. Graham-Rowe, “Sensors take the strain,” Nat. Photonics 1, 307–309 (2007).
[Crossref]

Hashimoto, K.

Hawkins, A. R.

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

He, J.-N.

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

Huang, G.

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Ji, X.

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

Kai, G.

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

Kawakatsu, H.

Li, E.

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

Li, H.-N.

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

Lia, X.-jin

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

Llobera, A.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Ou, J.

Z. Zhou and J. Ou, “Techniques of temperature compensation for FBG strain sensors used in long-term structural monitoring,” Proc. SPIE, 167–172 (2005).
[Crossref]

Plaza, J. A.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Qiao, X.

Qiu, C.-jun

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

Qu, W.

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

Ren, L.

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

Rzhavin, Y. I.

Y. I. Rzhavin, “Fiber-optic polarization pressure sensor,” Meas. Tech. 45, 738–741 (2002).
[Crossref]

Salinas, I.

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Schmidt, H.

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

Song, G.

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

Toshiyoshi, H.

Wang, Q.

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Worhoff, K.

Xi, J.

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

Yan, L.

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Yin, D.

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

Yuan, S.

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

Zhang, W.

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

Zhao, Q.

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

Zhou, Z.

Z. Zhou and J. Ou, “Techniques of temperature compensation for FBG strain sensors used in long-term structural monitoring,” Proc. SPIE, 167–172 (2005).
[Crossref]

Appl. Phys. Lett. (1)

D. Yin, D. W. Deamer, H. Schmidt, J. P. Barber, and A. R. Hawkins, “Integrated optical waveguides with liquid cores,” Appl. Phys. Lett. 85, 3477–3479 (2004).
[Crossref]

Chin. Opt. Lett. (1)

IEEE Photon. Technol. Lett. (1)

W. Zhang, X. Dong, Q. Zhao, G. Kai, and S. Yuan, “FBG-type sensor for simultaneous measurement of force (or displacement) and temperature based on bilateral cantilever beam,” IEEE Photon. Technol. Lett. 13, 1340–1342 (2001).
[Crossref]

IEEE Trans. Appl. Supercond. (1)

Q. Wang, Z. Fen, F. Deng, G. Huang, L. Yan, and Y. Dai, “Fiber Bragg gratings for strain sensing in high temperature superconducting magnet,” IEEE Trans. Appl. Supercond. 17, 2377–2380 (2007).
[Crossref]

Int. J. Nonlinear Sci. Numer. Simul. (1)

X.-jin Lia, C.-jun Qiu, Y.-long Deng, W. Qu, and J.-N. He, “An MEMS optical fiber pressure sensor based on a square silicon diaphragm: numerical simulation and experimental verification,” Int. J. Nonlinear Sci. Numer. Simul. 11, 225–229 (2010).
[Crossref]

J. Lightwave Technol. (1)

J. Microelectromech. Syst. (1)

J. A. Plaza, A. Llobera, C. Dominguez, J. Esteve, I. Salinas, J. Garcia, and J. Berganzo, “BESOI-based integrated optical silicon accelerator,” J. Microelectromech. Syst. 13, 355–364 (2004).
[Crossref]

Meas. Sci. Technol. (1)

W. Zhang, E. Li, J. Xi, J. Chicharo, and X. Dong, “Novel temperature-independent FBG-type force sensor,” Meas. Sci. Technol. 16, 1600–1604 (2005).
[Crossref]

Meas. Tech. (1)

Y. I. Rzhavin, “Fiber-optic polarization pressure sensor,” Meas. Tech. 45, 738–741 (2002).
[Crossref]

Nat. Photonics (1)

D. Graham-Rowe, “Sensors take the strain,” Nat. Photonics 1, 307–309 (2007).
[Crossref]

Org. Photon. Mater. Dev. IV (1)

L. Eldada, “Polymer integrated optics: promise vs. practicality,” Org. Photon. Mater. Dev. IV 4642, 11–22 (2002).

Smart Mater. Struct. (1)

L. Ren, J. Chen, H.-N. Li, G. Song, and X. Ji, “Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model,” Smart Mater. Struct. 18, 035015 (2009).
[Crossref]

Other (1)

Z. Zhou and J. Ou, “Techniques of temperature compensation for FBG strain sensors used in long-term structural monitoring,” Proc. SPIE, 167–172 (2005).
[Crossref]

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Figures (7)
Fig. 1
Fig. 1 Sketch of the structure used for strain amplification. The structure comprises two clamped beams joined together at an angle π − 2θ by a stiff center boss. A force F to be measured is applied to the center boss. At a specific angle, 0 < θ < π/2, the longitudinal strain in the Bragg grating (green) is maximized for a fixed force F.

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Fig. 2
Fig. 2 Normalized longitudinal strain εℓ (θ)/εℓ (π/2) as function of beam angle θ shown for four different aspect ratios L/H. As the aspect ratio of the beam increases, the strain is increased and the peak of maximum strain shifts towards lower angles. For the aspect ratio L/H = 10 results from a FEM calculation are also shown (• symbol); the FEM results are seen to agree well with the analytical calculation.

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Fig. 3
Fig. 3 The MBG sensor consists of a u-shaped waveguide connecting the fiber connect grooves at the bottom to the double beam sensing element at the top.

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Fig. 4
Fig. 4 Process flow for the sensor. Starting with an APOX wafer (a), 2.4 μm SiON is deposited using PECVD (b) in which a waveguide core and Bragg grating is written using EBL and AOE (c). A 4.8 μm thick layer of BPSG is deposited using PECVD (d) and a membrane is etched from the backside using AOE and DRIE (e). Finally the fiber grooves are made using AOE and DRIE (f) and the double beam is then released from from the membrane in an AOE etch which also defines the waveguide cladding (g).

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Fig. 5
Fig. 5 a) The finished chip with the waveguide (u-shaped) extending from the two fiber grooves at the bottom of the chip to the double beam at the top of the chip. b) The final double beam waveguide structure after dicing. A small amount of residues from the carrier membrane are seen around the double beam. With a thickness of < 50 nm such residues have almost no effect on the beam deflection.

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Fig. 6
Fig. 6 (a) The measured reflection spectra at three different loads. The average full width half maximum is 2.3 nm. (b) The measured change in Bragg wavelength as function of applied force. The measured Bragg wavelength shifts are seen to be in good agreement with the model calculations. The sensitivity is found to −14 nm/N.

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Fig. 7
Fig. 7 The change in Bragg wavelength due to temperature starting from 23.9°C. From the linear fit the temperature sensitivity is found to 30 pm/°C.

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Equations (12)

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

λ B = 2 n avg Λ ,
Δ λ B λ B = ( α + ζ ) Δ T + ( 1 − p e ) ε ℓ ,
F = 2 V cos θ − 2 N sin θ ,
w L sin θ = − u L cos θ .
u L = L ε ℓ = N L / ( E W H ) ,
E I w ″′ − N w ″ = q ,
N = − F  tan θ 2 ( tan  θ  sin  θ  + ( H L ) 2 cos θ ) ,
ε ℓ = − F 2 E W H tan  θ  ( tan  θ  sin  θ  + ( H L ) 2 cos θ ) .
θ max = arcsin H L 2 − H 2 = arctan H L 2 − 2 H 2 ≃ H L ,
ε ℓ max = − F 2 E W H L 2 H 1 − ( H L ) 2 ≃ − F L 4 E W H 2 ,
w ( x ) = w L ( ϰ x − sin ϰ x ) sin ϰ L + ( 1 − cos ϰ L ) ( cos ϰ x − 1 ) 2 ( cos ϰ L − 1 ) + ϰ L sin ϰ L
≃ w L x 2 ( 3 L − 2 x ) / L 3 + 𝒪 ( ϰ 2 )

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