Abstract

A chip-surface optical coupler based on a vertically curved Si waveguide was demonstrated for coupling with high-numerical-aperture single-mode optical fibers with a mode-field diameter of 5 µm. This device features a dome-like SiO2 coupler cap, which acts as collimation lens. We succeeded in fabricating this structure using an isotropic SiO2 deposition technique employing plasma-enhanced chemical vapor deposition and obtained a light output that approximates that of a 5-µm-waist Gaussian beam. The fabricated coupler showed a coupling loss of less than 4.2 dB and a 0.5-dB-loss bandwidth above 150 nm for TE-polarized light.

© 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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References

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  1. W. S. Zaoui, A. Kunze, W. Vogel, M. Berroth, J. Butschke, F. Letzkus, and J. Burghartz, “Bridging the gap between optical fibers and silicon photonic integrated circuits,” Opt. Express 22(2), 1277–1286 (2014).
    [Crossref] [PubMed]
  2. A. Bozzola, L. Carroll, D. Gerace, I. Cristiani, and L. C. Andreani, “Optimising apodized grating couplers in a pure SOI platform to -0.5 dB coupling efficiency,” Opt. Express 23(12), 16289–16304 (2015).
    [Crossref] [PubMed]
  3. C. Li, H. Zhang, M. Yu, and G. Q. Lo, “CMOS-compatible high efficiency double-etched apodized waveguide grating coupler,” Opt. Express 21(7), 7868–7874 (2013).
    [Crossref] [PubMed]
  4. Z. Wang, Y. Tang, L. Wosinski, and S. He, “Experimental demonstration of a high-efficiency polarization splitter based on a one-dimensional grating with a Bragg reflector underneath,” IEEE Photonics Technol. Lett. 22(21), 1568–1570 (2010).
    [Crossref]
  5. W. D. Sacher, Y. Huang, L. Ding, B. J. F. Taylor, H. Jayatilleka, G.-Q. Lo, and J. K. S. Poon, “Wide bandwidth and high coupling efficiency Si3N4-on-SOI dual-level grating coupler,” Opt. Express 22(9), 10938–10947 (2014).
    [Crossref] [PubMed]
  6. D. Vermeulen, S. Selvaraja, P. Verheyen, G. Lepage, W. Bogaerts, P. Absil, D. Van Thourhout, and G. Roelkens, “High-efficiency fiber-to-chip grating couplers realized using an advanced CMOS-compatible silicon-on-insulator platform,” Opt. Express 18(17), 18278–18283 (2010).
    [Crossref] [PubMed]
  7. L. Carroll, D. Gerace, I. Cristiani, and L. C. Andreani, “Optimizing polarization-diversity couplers for Si-photonics: reaching the -1dB coupling efficiency threshold,” Opt. Express 22(12), 14769–14781 (2014).
    [Crossref] [PubMed]
  8. J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
    [Crossref]
  9. M. Wood, P. Sun, and R. M. Reano, “Compact cantilever couplers for low-loss fiber coupling to silicon photonic integrated circuits,” Opt. Express 20(1), 164–172 (2012).
    [Crossref] [PubMed]
  10. T. Yoshida, S. Tajima, R. Takei, M. Mori, N. Miura, and Y. Sakakibara, “Vertical silicon waveguide coupler bent by ion implantation,” Opt. Express 23(23), 29449–29456 (2015).
    [Crossref] [PubMed]
  11. T. Yoshida, E. Omoda, Y. Atsumi, T. Nishi, S. Tajima, N. Miura, M. Mori, and Y. Sakakibara, “Vertically curved Si waveguide coupler with low loss and flat wavelength window,” J. Lightwave Technol. 34(7), 1567–1571 (2016).
    [Crossref]
  12. Y. Atsumi, T. Yoshida, E. Omoda, and Y. Sakakibara, “Design of compact surface optical coupler based on vertically curved silicon waveguide for high-numerical aperture single-mode optical fiber,” Jpn. J. Appl. Phys. 56(9), 090307 (2017).
    [Crossref]
  13. T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
    [Crossref]
  14. W. D. Sacher, Y. Huang, G.-Q. Lo, and J. K. S. Poon, “Multilayer silicon nitride-on-silicon integrated photonic platforms and devices,” J. Lightwave Technol. 33(4), 901–910 (2015).
    [Crossref]
  15. H. Park, S. Kim, J. Park, J. Joo, and G. Kim, “A fiber-to-chip coupler based on Si/SiON cascaded tapers for Si photonic chips,” Opt. Express 21(24), 29313–29319 (2013).
    [Crossref] [PubMed]
  16. Y. Maegami, M. Okano, G. Cong, M. Ohno, and K. Yamada, “Completely CMOS compatible SiN-waveguide-based fiber coupling structure for Si wire waveguides,” Opt. Express 24(15), 16856–16865 (2016).
    [Crossref] [PubMed]
  17. M. Papes, P. Cheben, D. Benedikovic, J. H. Schmid, J. Pond, R. Halir, A. Ortega-Moñux, G. Wangüemert-Pérez, W. N. Ye, D. X. Xu, S. Janz, M. Dado, and V. Vašinek, “Fiber-chip edge coupler with large mode size for silicon photonic wire waveguides,” Opt. Express 24(5), 5026–5038 (2016).
    [Crossref] [PubMed]
  18. Q. Fang, T.-Y. Liow, J. F. Song, C. W. Tan, M. B. Yu, G. Q. Lo, and D.-L. Kwong, “Suspended optical fiber-to-waveguide mode size converter for silicon photonics,” Opt. Express 18(8), 7763–7769 (2010).
    [Crossref] [PubMed]
  19. A. Dewanjee, J. S. Aitchison, and M. Mojahedi, “Experimental demonstration of a high efficiency compact bilayer inverse taper edge coupler for Si photonics,” in Proc. Int. Conf. Optical Fiber Communication, TuG2.2 (2016).
    [Crossref]
  20. M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

2017 (1)

Y. Atsumi, T. Yoshida, E. Omoda, and Y. Sakakibara, “Design of compact surface optical coupler based on vertically curved silicon waveguide for high-numerical aperture single-mode optical fiber,” Jpn. J. Appl. Phys. 56(9), 090307 (2017).
[Crossref]

2016 (3)

2015 (3)

2014 (4)

2013 (2)

2012 (1)

2010 (3)

2002 (1)

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

Absil, P.

Amemiya, T.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Andreani, L. C.

Arai, S.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Atsumi, Y.

Y. Atsumi, T. Yoshida, E. Omoda, and Y. Sakakibara, “Design of compact surface optical coupler based on vertically curved silicon waveguide for high-numerical aperture single-mode optical fiber,” Jpn. J. Appl. Phys. 56(9), 090307 (2017).
[Crossref]

T. Yoshida, E. Omoda, Y. Atsumi, T. Nishi, S. Tajima, N. Miura, M. Mori, and Y. Sakakibara, “Vertically curved Si waveguide coupler with low loss and flat wavelength window,” J. Lightwave Technol. 34(7), 1567–1571 (2016).
[Crossref]

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Benedikovic, D.

Berroth, M.

Bogaerts, W.

Bozzola, A.

Burghartz, J.

Butschke, J.

Carroll, L.

Cheben, P.

Cong, G.

Cristiani, I.

Dado, M.

Ding, L.

Fang, Q.

Gerace, D.

Halir, R.

Hayashi, Y.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

He, S.

Z. Wang, Y. Tang, L. Wosinski, and S. He, “Experimental demonstration of a high-efficiency polarization splitter based on a one-dimensional grating with a Bragg reflector underneath,” IEEE Photonics Technol. Lett. 22(21), 1568–1570 (2010).
[Crossref]

Huang, Y.

Janz, S.

Jayatilleka, H.

Joo, J.

Kang, J.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Kim, G.

Kim, S.

Kuno, Y.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Kunze, A.

Kwong, D.-L.

Larouche, C.

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

Latrasse, C.

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

Lepage, G.

Letzkus, F.

Li, C.

Liow, T.-Y.

Lo, G. Q.

Lo, G.-Q.

Maegami, Y.

Miura, N.

Mori, M.

Morita, H.

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

Nishi, T.

Nishiyama, N.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Ohno, M.

Okano, M.

Omoda, E.

Y. Atsumi, T. Yoshida, E. Omoda, and Y. Sakakibara, “Design of compact surface optical coupler based on vertically curved silicon waveguide for high-numerical aperture single-mode optical fiber,” Jpn. J. Appl. Phys. 56(9), 090307 (2017).
[Crossref]

T. Yoshida, E. Omoda, Y. Atsumi, T. Nishi, S. Tajima, N. Miura, M. Mori, and Y. Sakakibara, “Vertically curved Si waveguide coupler with low loss and flat wavelength window,” J. Lightwave Technol. 34(7), 1567–1571 (2016).
[Crossref]

Ortega-Moñux, A.

Painchaud, Y.

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

Papes, M.

Park, H.

Park, J.

Pelletier, F.

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

Picard, M.-J.

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

Pond, J.

Poon, J. K. S.

Poulin, M.

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

Reano, R. M.

Roelkens, G.

Sacher, W. D.

Sakakibara, Y.

Schmid, J. H.

Selvaraja, S.

Shoji, T.

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

Song, J. F.

Sun, P.

Suzuki, J.

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Tajima, S.

Takei, R.

Tan, C. W.

Tang, Y.

Z. Wang, Y. Tang, L. Wosinski, and S. He, “Experimental demonstration of a high-efficiency polarization splitter based on a one-dimensional grating with a Bragg reflector underneath,” IEEE Photonics Technol. Lett. 22(21), 1568–1570 (2010).
[Crossref]

Taylor, B. J. F.

Tsuchizawa, T.

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

Van Thourhout, D.

Vašinek, V.

Verheyen, P.

Vermeulen, D.

Vogel, W.

Wang, Z.

Z. Wang, Y. Tang, L. Wosinski, and S. He, “Experimental demonstration of a high-efficiency polarization splitter based on a one-dimensional grating with a Bragg reflector underneath,” IEEE Photonics Technol. Lett. 22(21), 1568–1570 (2010).
[Crossref]

Wangüemert-Pérez, G.

Watanabe, T.

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

Wood, M.

Wosinski, L.

Z. Wang, Y. Tang, L. Wosinski, and S. He, “Experimental demonstration of a high-efficiency polarization splitter based on a one-dimensional grating with a Bragg reflector underneath,” IEEE Photonics Technol. Lett. 22(21), 1568–1570 (2010).
[Crossref]

Xu, D. X.

Yamada, K.

Y. Maegami, M. Okano, G. Cong, M. Ohno, and K. Yamada, “Completely CMOS compatible SiN-waveguide-based fiber coupling structure for Si wire waveguides,” Opt. Express 24(15), 16856–16865 (2016).
[Crossref] [PubMed]

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

Ye, W. N.

Yoshida, T.

Yu, M.

Yu, M. B.

Zaoui, W. S.

Zhang, H.

Appl. Phys. Express (1)

J. Kang, Y. Atsumi, Y. Hayashi, J. Suzuki, Y. Kuno, T. Amemiya, N. Nishiyama, and S. Arai, “50 Gbps data transmission through amorphous silicon interlayer grating couplers with metal mirrors,” Appl. Phys. Express 7(3), 032202 (2014).
[Crossref]

Electron. Lett. (1)

T. Shoji, T. Tsuchizawa, T. Watanabe, K. Yamada, and H. Morita, “Low loss mode size converter from 0.3-µm square Si wire waveguides to single-mode fibers,” Electron. Lett. 38(25), 1669–1670 (2002).
[Crossref]

IEEE Photonics Technol. Lett. (1)

Z. Wang, Y. Tang, L. Wosinski, and S. He, “Experimental demonstration of a high-efficiency polarization splitter based on a one-dimensional grating with a Bragg reflector underneath,” IEEE Photonics Technol. Lett. 22(21), 1568–1570 (2010).
[Crossref]

J. Lightwave Technol. (2)

Jpn. J. Appl. Phys. (1)

Y. Atsumi, T. Yoshida, E. Omoda, and Y. Sakakibara, “Design of compact surface optical coupler based on vertically curved silicon waveguide for high-numerical aperture single-mode optical fiber,” Jpn. J. Appl. Phys. 56(9), 090307 (2017).
[Crossref]

Opt. Express (12)

H. Park, S. Kim, J. Park, J. Joo, and G. Kim, “A fiber-to-chip coupler based on Si/SiON cascaded tapers for Si photonic chips,” Opt. Express 21(24), 29313–29319 (2013).
[Crossref] [PubMed]

Y. Maegami, M. Okano, G. Cong, M. Ohno, and K. Yamada, “Completely CMOS compatible SiN-waveguide-based fiber coupling structure for Si wire waveguides,” Opt. Express 24(15), 16856–16865 (2016).
[Crossref] [PubMed]

M. Papes, P. Cheben, D. Benedikovic, J. H. Schmid, J. Pond, R. Halir, A. Ortega-Moñux, G. Wangüemert-Pérez, W. N. Ye, D. X. Xu, S. Janz, M. Dado, and V. Vašinek, “Fiber-chip edge coupler with large mode size for silicon photonic wire waveguides,” Opt. Express 24(5), 5026–5038 (2016).
[Crossref] [PubMed]

Q. Fang, T.-Y. Liow, J. F. Song, C. W. Tan, M. B. Yu, G. Q. Lo, and D.-L. Kwong, “Suspended optical fiber-to-waveguide mode size converter for silicon photonics,” Opt. Express 18(8), 7763–7769 (2010).
[Crossref] [PubMed]

W. D. Sacher, Y. Huang, L. Ding, B. J. F. Taylor, H. Jayatilleka, G.-Q. Lo, and J. K. S. Poon, “Wide bandwidth and high coupling efficiency Si3N4-on-SOI dual-level grating coupler,” Opt. Express 22(9), 10938–10947 (2014).
[Crossref] [PubMed]

D. Vermeulen, S. Selvaraja, P. Verheyen, G. Lepage, W. Bogaerts, P. Absil, D. Van Thourhout, and G. Roelkens, “High-efficiency fiber-to-chip grating couplers realized using an advanced CMOS-compatible silicon-on-insulator platform,” Opt. Express 18(17), 18278–18283 (2010).
[Crossref] [PubMed]

L. Carroll, D. Gerace, I. Cristiani, and L. C. Andreani, “Optimizing polarization-diversity couplers for Si-photonics: reaching the -1dB coupling efficiency threshold,” Opt. Express 22(12), 14769–14781 (2014).
[Crossref] [PubMed]

M. Wood, P. Sun, and R. M. Reano, “Compact cantilever couplers for low-loss fiber coupling to silicon photonic integrated circuits,” Opt. Express 20(1), 164–172 (2012).
[Crossref] [PubMed]

T. Yoshida, S. Tajima, R. Takei, M. Mori, N. Miura, and Y. Sakakibara, “Vertical silicon waveguide coupler bent by ion implantation,” Opt. Express 23(23), 29449–29456 (2015).
[Crossref] [PubMed]

W. S. Zaoui, A. Kunze, W. Vogel, M. Berroth, J. Butschke, F. Letzkus, and J. Burghartz, “Bridging the gap between optical fibers and silicon photonic integrated circuits,” Opt. Express 22(2), 1277–1286 (2014).
[Crossref] [PubMed]

A. Bozzola, L. Carroll, D. Gerace, I. Cristiani, and L. C. Andreani, “Optimising apodized grating couplers in a pure SOI platform to -0.5 dB coupling efficiency,” Opt. Express 23(12), 16289–16304 (2015).
[Crossref] [PubMed]

C. Li, H. Zhang, M. Yu, and G. Q. Lo, “CMOS-compatible high efficiency double-etched apodized waveguide grating coupler,” Opt. Express 21(7), 7868–7874 (2013).
[Crossref] [PubMed]

Other (2)

A. Dewanjee, J. S. Aitchison, and M. Mojahedi, “Experimental demonstration of a high efficiency compact bilayer inverse taper edge coupler for Si photonics,” in Proc. Int. Conf. Optical Fiber Communication, TuG2.2 (2016).
[Crossref]

M.-J. Picard, Y. Painchaud, C. Latrasse, C. Larouche, F. Pelletier, and M. Poulin, “Novel spot-size converter for optical fiber to sub-µm silicon waveguide coupling with low loss, low wavelength dependence and high tolerance to alignment,” in Proceedings of the European Conference on Optical Communication (ECOC) (2015), pp. 1–3.

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Figures (7)

Fig. 1
Fig. 1 Elephant couplers (a) SEM images of vertically curved Si waveguides deformed by IIB method (b) Propagating electric-field profile of the 5-µm-beam-spot elephant coupler.
Fig. 2
Fig. 2 (a) Schematic of the vertically curved Si waveguide fabricated using the IIB method. (b) SEM image of the curved waveguide with a taper length of 9 µm. Inset shows a top-view of the Si taper before the IIB process.
Fig. 3
Fig. 3 (a) Schematic of the dome-like SiO2 coupler-top fabricated by applying isotropically SiO2 deposition using PECVD. (b) SEM image of the fabricated elephant coupler with SiO2 dome.
Fig. 4
Fig. 4 Cross-sectional SIM image of the elephant coupler with a 9-µm-long Si taper. A tungsten sacrifice layer for the FIB milling process was temporarily depositted on the body of the device.
Fig. 5
Fig. 5 Measurement of the FFP:(a) setup and (b) profiles.
Fig. 6
Fig. 6 Measurement of coupling loss: (a) setup and (b) coupling spectra.
Fig. 7
Fig. 7 Alignment sensitivities for coupling loss in fiber angle: (a) fiber angle definition (b) measurement result.

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