Abstract

In optical frequency domain imaging (OFDI) or swept-source optical coherence tomography, balanced detection is required to suppress relative intensity noise (RIN). A regular implementation of balanced detection by combining reference and sample arm signal in a 50/50 coupler and detecting the differential output with a balanced receiver is however, not perfect. Since the splitting ratio of the 50/50 coupler is wavelength dependent, RIN is not optimally canceled at the edges of the wavelength sweep. The splitting ratio has a nearly linear shift of 0.4% per nanometer. This brings as much as ±12% deviation at the margins of wavelength-swept range centered at 1060nm. We demonstrate a RIN suppression of 33dB by spectrally corrected balanced detection, 11dB more that regular balanced detection.

©2007 Optical Society of America

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2007 (2)

2006 (5)

2005 (7)

B. Grajciar, M. Pircher, A. F. Fercher, and R. A. Leitgeb, “Parallel Fourier domain optical coherence tomography for in vivo measurement of the human eye,” Opt. Express 13, 1131–1137 (2005).
[Crossref] [PubMed]

B. H. Park, M. C. Pierce, B. Cense, S. H. Yun, M. Mujat, G. J. Tearney, B. E. Bouma, and J. F. de Boer, “Real-time fiber-based multi-functional spectral-domain optical coherence tomography at 1.3 mu m,” Opt. Express 13, 3931–3944 (2005).
[Crossref] [PubMed]

J. Zhang and Z. P. Chen, “In vivo blood flow imaging by a swept laser source based Fourier domain optical Doppler tomography,” Opt. Express 13, 7449–7457 (2005).
[Crossref] [PubMed]

W. Y. Oh, S. H. Yun, G. J. Tearney, and B. E. Bouma, “115 kHz tuning repetition rate ultrahigh-speed wavelength-swept semiconductor laser,” Opt. Lett. 30, 3159–3161 (2005).
[Crossref] [PubMed]

R. Huber, M. Wojtkowski, J. G. Fujimoto, J. Y. Jiang, and A. E. Cable, “Three-dimensional and C-mode OCT imaging with a compact, frequency swept laser source at 1300 nm,” Opt. Express 13, 10523–10538 (2005).
[Crossref] [PubMed]

Y. Yasuno, V. D. Madjarova, S. Makita, M. Akiba, A. Morosawa, C. Chong, T. Sakai, K. P. Chan, M. Itoh, and T. Yatagai, “Three-dimensional and high-speed swept-source optical coherence tomography for in vivo investigation of human anterior eye segments,” Opt. Express 13, 10652–10664 (2005).
[Crossref] [PubMed]

T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
[Crossref] [PubMed]

2004 (4)

N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
[Crossref]

S. Yan, D. Piao, Y. Chen, and Q. Zhu, “Digital signal processor-based real-time optical Doppler tomography system,” Journal of biomedical optics 9, 454–463 (2004).
[Crossref] [PubMed]

N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
[Crossref] [PubMed]

B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
[Crossref] [PubMed]

2003 (6)

2002 (1)

M. Wojtkowski, R. Leitgeb, A. Kowalczyk, T. Bajraszewski, and A. F. Fercher, “In vivo human retinal imaging by Fourier domain optical coherence tomography,” J. Biomed. Opt. 7, 457–463 (2002).
[Crossref] [PubMed]

2000 (1)

1999 (1)

T. Mitsui, “Dynamic range of optical reflectometry with spectral interferometry,” Japanese Journal of Applied Physics Part 1-Regular Papers Short Notes & Review Papers 38, 6133–6137 (1999).

1998 (1)

G. Hausler and M. W. Lindner, “Coherence Radar and Spectral Radar - new tools for dermatological diagnosis,” J. Biomed. Opt. 3, 21–31 (1998).
[Crossref]

1995 (1)

A. F. Fercher, C. K. Hitzenberger, G. Kamp, and S. Y. El-Zaiat, “Measurement of intraocular distances by backscattering spectral interferometry,” Opt. Commun. 117, 43–48 (1995).
[Crossref]

1992 (1)

W. V. Sorin and D. M. Baney, “A Simple Intensity Noise-Reduction Technique for Optical Low- Coherence Reflectometry,” IEEE Photonics Technology Letters 4, 1404–1406 (1992).
[Crossref]

1991 (1)

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical Coherence Tomography,” Science 254, 1178–1181 (1991).
[Crossref] [PubMed]

1962 (1)

L. Mandel and E. Wolf, “Measures of Bandwidth and Coherence Time in Optics,” Proceedings of the Physical Society of London 80, 894–897 (1962).
[Crossref]

Adler, D. C.

Akiba, M.

Bajraszewski, T.

M. Wojtkowski, R. Leitgeb, A. Kowalczyk, T. Bajraszewski, and A. F. Fercher, “In vivo human retinal imaging by Fourier domain optical coherence tomography,” J. Biomed. Opt. 7, 457–463 (2002).
[Crossref] [PubMed]

Baney, D. M.

W. V. Sorin and D. M. Baney, “A Simple Intensity Noise-Reduction Technique for Optical Low- Coherence Reflectometry,” IEEE Photonics Technology Letters 4, 1404–1406 (1992).
[Crossref]

Boudoux, C.

Bouma, B. E.

T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
[Crossref] [PubMed]

B. H. Park, M. C. Pierce, B. Cense, S. H. Yun, M. Mujat, G. J. Tearney, B. E. Bouma, and J. F. de Boer, “Real-time fiber-based multi-functional spectral-domain optical coherence tomography at 1.3 mu m,” Opt. Express 13, 3931–3944 (2005).
[Crossref] [PubMed]

W. Y. Oh, S. H. Yun, G. J. Tearney, and B. E. Bouma, “115 kHz tuning repetition rate ultrahigh-speed wavelength-swept semiconductor laser,” Opt. Lett. 30, 3159–3161 (2005).
[Crossref] [PubMed]

N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
[Crossref]

N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
[Crossref] [PubMed]

B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
[Crossref] [PubMed]

B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
[Crossref] [PubMed]

S. H. Yun, C. Boudoux, G. J. Tearney, and B. E. Bouma, “High-speed wavelength-swept semiconductor laser with a polygon-scanner-based wavelength filter,” Opt. Lett. 28, 1981–1983 (2003).
[Crossref] [PubMed]

J. F. de Boer, B. Cense, B. H. Park, M. C. Pierce, G. J. Tearney, and B. E. Bouma, “Improved signal-to-noise ratio in spectral-domain compared with time-domain optical coherence tomography,” Opt. Lett. 28, 2067–2069 (2003).
[Crossref] [PubMed]

S. H. Yun, G. J. Tearney, J. F. de Boer, N. Iftimia, and B. E. Bouma, “High-speed optical frequency-domain imaging,” Opt. Express 11, 2953–2963 (2003).
[Crossref] [PubMed]

S. H. Yun, G. J. Tearney, B. J. Vakoc, M. Shishkov, W. Y. Oh, A. E. Desjardins, M. J. Suter, R. C. Chan, J. A. Evans, I. K. Jang, N. S. Nishioka, J. F. de Boer, and B. E. Bouma, “Comprehensive volumetric optical microscopy in vivo,” Nature Medicine 12, 1429–1433 (1).
[Crossref]

W. Y. Oh, S. H. Yun, B. J. Vakoc, G. J. Tearney, and B. E. Bouma, “Ultrahigh-speed optical frequency domain imaging and application to laser ablation monitoring,” Appl. Phys. Lett.88 (2006).
[Crossref]

Cable, A. E.

Cense, B.

Y. Zhang, B. Cense, J. Rha, R. S. Jonnal, W. Gao, R. J. Zawadzki, J. S. Werner, S. Jones, S. Olivier, and D. T. Miller, “High-speed volumetric imaging of cone photoreceptors with adaptive optics spectral-domain optical coherence tomography,” Opt. Express 14, 4380–4394 (2006).
[Crossref] [PubMed]

T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
[Crossref] [PubMed]

B. H. Park, M. C. Pierce, B. Cense, S. H. Yun, M. Mujat, G. J. Tearney, B. E. Bouma, and J. F. de Boer, “Real-time fiber-based multi-functional spectral-domain optical coherence tomography at 1.3 mu m,” Opt. Express 13, 3931–3944 (2005).
[Crossref] [PubMed]

B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
[Crossref] [PubMed]

N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
[Crossref] [PubMed]

N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
[Crossref]

B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
[Crossref] [PubMed]

J. F. de Boer, B. Cense, B. H. Park, M. C. Pierce, G. J. Tearney, and B. E. Bouma, “Improved signal-to-noise ratio in spectral-domain compared with time-domain optical coherence tomography,” Opt. Lett. 28, 2067–2069 (2003).
[Crossref] [PubMed]

Chan, K. P.

Chan, R. C.

S. H. Yun, G. J. Tearney, B. J. Vakoc, M. Shishkov, W. Y. Oh, A. E. Desjardins, M. J. Suter, R. C. Chan, J. A. Evans, I. K. Jang, N. S. Nishioka, J. F. de Boer, and B. E. Bouma, “Comprehensive volumetric optical microscopy in vivo,” Nature Medicine 12, 1429–1433 (1).
[Crossref]

Chang, W.

D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical Coherence Tomography,” Science 254, 1178–1181 (1991).
[Crossref] [PubMed]

Chen, T. C.

H. Lim, M. Mujat, C. Kerbage, E. C. Lee, Y. Chen, T. C. Chen, and J. F. de Boer, “High-speed imaging of human retina in vivo with swept-source optical coherence tomography,” Opt. Express 14, 12902–12908 (2006).
[Crossref] [PubMed]

T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
[Crossref] [PubMed]

N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
[Crossref]

N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
[Crossref] [PubMed]

B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
[Crossref] [PubMed]

B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
[Crossref] [PubMed]

Chen, Y.

H. Lim, M. Mujat, C. Kerbage, E. C. Lee, Y. Chen, T. C. Chen, and J. F. de Boer, “High-speed imaging of human retina in vivo with swept-source optical coherence tomography,” Opt. Express 14, 12902–12908 (2006).
[Crossref] [PubMed]

S. Yan, D. Piao, Y. Chen, and Q. Zhu, “Digital signal processor-based real-time optical Doppler tomography system,” Journal of biomedical optics 9, 454–463 (2004).
[Crossref] [PubMed]

Chen, Z. P.

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T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
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J. F. de Boer, B. Cense, B. H. Park, M. C. Pierce, G. J. Tearney, and B. E. Bouma, “Improved signal-to-noise ratio in spectral-domain compared with time-domain optical coherence tomography,” Opt. Lett. 28, 2067–2069 (2003).
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W. Y. Oh, S. H. Yun, B. J. Vakoc, G. J. Tearney, and B. E. Bouma, “Ultrahigh-speed optical frequency domain imaging and application to laser ablation monitoring,” Appl. Phys. Lett.88 (2006).
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T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
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N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
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N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
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B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
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B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
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J. F. de Boer, B. Cense, B. H. Park, M. C. Pierce, G. J. Tearney, and B. E. Bouma, “Improved signal-to-noise ratio in spectral-domain compared with time-domain optical coherence tomography,” Opt. Lett. 28, 2067–2069 (2003).
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T. C. Chen, B. Cense, M. C. Pierce, N. Nassif, B. H. Park, S. H. Yun, B. R. White, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Spectral domain optical coherence tomography: ultra-high speed, ultra-high resolution ophthalmic imaging,” Arch Ophthalmol 123, 1715–1720 (2005).
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N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
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B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
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B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
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D. Huang, E. A. Swanson, C. P. Lin, J. S. Schuman, W. G. Stinson, W. Chang, M. R. Hee, T. Flotte, K. Gregory, C. A. Puliafito, and J. G. Fujimoto, “Optical Coherence Tomography,” Science 254, 1178–1181 (1991).
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[Crossref] [PubMed]

B. H. Park, M. C. Pierce, B. Cense, S. H. Yun, M. Mujat, G. J. Tearney, B. E. Bouma, and J. F. de Boer, “Real-time fiber-based multi-functional spectral-domain optical coherence tomography at 1.3 mu m,” Opt. Express 13, 3931–3944 (2005).
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W. Y. Oh, S. H. Yun, G. J. Tearney, and B. E. Bouma, “115 kHz tuning repetition rate ultrahigh-speed wavelength-swept semiconductor laser,” Opt. Lett. 30, 3159–3161 (2005).
[Crossref] [PubMed]

B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
[Crossref] [PubMed]

N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
[Crossref] [PubMed]

N. A. Nassif, B. Cense, B. H. Park, M. C. Pierce, S. H. Yun, B. E. Bouma, G. J. Tearney, T. C. Chen, and J. F. de Boer, “In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve,” in Opt. Express(2004), pp. 367–376.
[Crossref]

B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
[Crossref] [PubMed]

J. F. de Boer, B. Cense, B. H. Park, M. C. Pierce, G. J. Tearney, and B. E. Bouma, “Improved signal-to-noise ratio in spectral-domain compared with time-domain optical coherence tomography,” Opt. Lett. 28, 2067–2069 (2003).
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S. H. Yun, G. J. Tearney, B. J. Vakoc, M. Shishkov, W. Y. Oh, A. E. Desjardins, M. J. Suter, R. C. Chan, J. A. Evans, I. K. Jang, N. S. Nishioka, J. F. de Boer, and B. E. Bouma, “Comprehensive volumetric optical microscopy in vivo,” Nature Medicine 12, 1429–1433 (1).
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S. H. Yun, G. J. Tearney, B. J. Vakoc, M. Shishkov, W. Y. Oh, A. E. Desjardins, M. J. Suter, R. C. Chan, J. A. Evans, I. K. Jang, N. S. Nishioka, J. F. de Boer, and B. E. Bouma, “Comprehensive volumetric optical microscopy in vivo,” Nature Medicine 12, 1429–1433 (1).
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N. Nassif, B. Cense, B. H. Park, S. H. Yun, T. C. Chen, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “In vivo human retinal imaging by ultrahigh-speed spectral domain optical coherence tomography,” Opt. Lett. 29, 480–482 (2004).
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B. M. Hoeling, A. D. Fernandez, R. C. Haskell, E. Huang, W. R. Myers, D. C. Petersen, S. E. Ungersma, R. Y. Wang, M. E. Williams, and S. E. Fraser, “An optical coherence microscope for 3-dimensional imaging in developmental biology,” Opt. Express 6, 136–146 (2000).
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C. Kerbage, H. Lim, W. Sun, M. Mujat, and J. F. de Boer, “Large depth-high resolution full 3D imaging of the anterior segments of the eye using high speed optical frequency domain imaging,” Opt. Express 15, 7117–7125 (2007).
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E. C. W. Lee, J. F. de Boer, M. Mujat, H. Lim, and S. H. Yun, “In vivo optical frequency domain imaging of human retina and choroid,” Opt. Express 14, 4403–4411 (2006).
[Crossref] [PubMed]

S. H. Yun, G. J. Tearney, J. F. de Boer, N. Iftimia, and B. E. Bouma, “High-speed optical frequency-domain imaging,” Opt. Express 11, 2953–2963 (2003).
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B. R. White, M. C. Pierce, N. Nassif, B. Cense, B. H. Park, G. J. Tearney, B. E. Bouma, T. C. Chen, and J. F. de Boer, “In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography,” Opt. Express 11, 3490–3497 (2003).
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B. Cense, N. Nassif, T. C. Chen, M. C. Pierce, S. H. Yun, B. H. Park, B. E. Bouma, G. J. Tearney, and J. F. de Boer, “Ultrahigh-Resolution High-Speed Retinal Imaging Using Spectral-Domain Optical Coherence Tomography,” Opt. Express 12, 2435–2447 (2004).
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Figures (6)

Fig. 1.
Fig. 1. Schematic of the 1050nm OFDI system. The wavelength-swept laser is on the top-left [36]. A mirror in the tunable mirror served as the end reflector that doubles the free spectral range[19]. The imaging interferometer uses a 30/70 fiber coupler to split sample and reference arm light. They recombined at a 50/50 coupler. The two balanced detection configurations are illustrated in the bottom-left corner. SOA: semiconductor optical amplifier, PC: Polarization controller. The inset (top-right) is the swept laser spectra from the two 50/50 coupler outputs where the 50/50 splitting ratio is only valid around the central wavelengths.

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Fig. 2.
Fig. 2. (a) Digitized wavelength-sweep laser spectra from the two 50/50 coupler outputs. The 50/50 splitting ration is exact only around central part of the spectra. (b) The spectrally dependent channel splitting ratio of the coupler (dotted blue) and the polynomial fitting (solid red). The fitting curve is used to compensate the spectral dependent splitting ratio and improve the effectiveness of balanced detection.

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Fig. 3.
Fig. 3. The detection system noise consists of thermal and DAQ noise. Noise spectra were acquired in three data acquisition vertical ranges of 1, 2, and 4V peak-to-peak from left to right. Blue solid lines are the thermal plus DAQ noise measured when the optical input to the detector was blocked. Red dotted lines are DAQ noise when digitizer’s analog input is terminated with 50 ohm. A discrete Fourier transform of 1024 data points is used to assess the noise floor. Y-axis is in absolution unit 10log(pA2/Hz) calculated at the PIN detector output.

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Fig. 4.
Fig. 4. Fitting of shot plus RIN noise in three detection conditions. (a) Unbalanced detection, (b) Regular hardware balanced detection, and (c) Spectrally balanced detection. The dotted plots are experimental noise measurement after removal of thermal and DAQ noise. The red solid lines are the nonlinear fit by Origin 6.

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Fig. 5.
Fig. 5. The system noise characterization plotted as a function of the reference power for 1050nm OFDI after decomposition of four primary noise components: DAQ, thermal, shot, and RIN noise. The y-axis gives absolute noise power expressed as the noise current in decibel at the PIN detector. The symbols are experimental data, dashed lines are fits to the experimental data, and the solid lines are the decomposed four noise components. Hardware balanced detection suppressed about 22dB RIN. Spectral balance further suppressed 11dB. A reference power window where shot noise is larger than all other noise terms appears in spectral balanced detection. DAQ noise cannot be ignored especially at high digitizer vertical ranges (4V and 10V).

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Fig. 6.
Fig. 6. (a) and (b) are the depth profiles of spectrally balanced and directly balanced detections schemes, respectively. The strong peak to the left is from a mirror sample about 0.5 mm away from the reference mirror. The peak to the right is from the laser source, and two sidelobes are the mixing terms of the mirror sample and the laser source peak. Fig 6 (c) shows the subtraction of the software balanced from the hardware balanced depth profile, demonstrating a 5–8 dB noise suppression. In addition, the DC and common mode source noise peak are also reduced. The two side peaks around the source peak are still at the same level because they arise from the mixing of sample mirror and laser source signal, which are not common mode signals.

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Equations (9)

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I det ( k ) = I ref ( k ) + I s ( k ) + 2 I ref ( k ) I s ( k ) cos ( k · z ) ,
σ shot 2 = 2 a I ref , [ A 2 ⁄ Hz ]
σ RIN 2 = 2 τ coh I ref 2 , [ A 2 ⁄ Hz ]
σ total 2 = σ thermal 2 + σ shot 2 + σ RIN 2 + σ daq 2 , [ A 2 ⁄ Hz ]
SNR = 10 · log ( η P s h v · f A ) .
I s = η q P s h v .
S bal ( λ ) = S ch 1 ( λ ) ⁄ R ( λ ) − S ch 2 ( λ ) · R ( λ ) .
σ HB 2 = 2 × ( σ Thermal 2 + σ DAQ 2 ) + σ shot 2 + σ RIN , HB 2 = 19.9 + 15.6 + 66.0 = 101.5 p A 2 ⁄ Hz
σ SB 2 = 2 × ( σ Thermal 2 + σ DAQ 2 ) + σ shot 2 + σ RIN , SB 2 = 19.9 + 15.6 + 5.0 = 40.5 p A 2 ⁄ Hz

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