Abstract

In this paper, we report what we believe is a novel technique to overcome the depth-of-focus (DOF) limitation in optical coherence tomography (OCT). Using confocal optics on a sample arm, we scanned the illumination beam across the under-filled objective lens pupil plane by steering the beam at the pinhole using a microcylindrical lens. The detected interferometric signals from multiple distinctive apertures were digitally refocused, which is analogous to synthetic aperture radar (SAR). Using numerical simulations and imaging experiments, we verified that this technique can maintain a diffraction-limited transverse resolution along a DOF that is 10 times larger than the confocal parameter. The ability to extend the DOF without signal loss and sidelobe artifacts may ultimately overcome the DOF limitation in high-resolution OCT.

© 2017 Optical Society of America

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References

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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]

2016 (1)

E. Bo and L. Liu, “Spectral domain optical coherence tomography with extended depth-of-focus by aperture synthesis,” Proc. SPIE 10024, 1002451 (2016).
[Crossref]

2015 (1)

2014 (1)

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

2013 (1)

2011 (1)

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

2009 (1)

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

2008 (1)

2007 (2)

L. Liu, C. Liu, W. C. Howe, C. Sheppard, and N. Chen, “Binary-phase spatial filter for real-time swept-source optical coherence microscopy,” Opt. Lett. 32, 2375–2377 (2007).
[Crossref]

T. S. Ralston, D. L. Marks, P. S. Carney, and S. A. Boppart, “Interferometric synthetic aperture microscopy,” Nat. Phys. 3, 129–134 (2007).
[Crossref]

2006 (1)

2002 (1)

1992 (1)

1991 (3)

1989 (1)

1983 (1)

C. Sheppard, D. Hamilton, and I. Cox, “Optical microscopy with extended depth of field,” Proc. R. Soc. London Ser. A 387, 171–186 (1983).
[Crossref]

1978 (1)

Adhi, M.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Bachmann, A.

Baumal, C.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Bezerra, H. G.

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

Bo, E.

E. Bo and L. Liu, “Spectral domain optical coherence tomography with extended depth-of-focus by aperture synthesis,” Proc. SPIE 10024, 1002451 (2016).
[Crossref]

Boppart, S. A.

T. S. Ralston, D. L. Marks, P. S. Carney, and S. A. Boppart, “Interferometric synthetic aperture microscopy,” Nat. Phys. 3, 129–134 (2007).
[Crossref]

Bouma, B. E.

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Carney, P. S.

T. S. Ralston, D. L. Marks, P. S. Carney, and S. A. Boppart, “Interferometric synthetic aperture microscopy,” Nat. Phys. 3, 129–134 (2007).
[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, and C. A. Puliafito, “Optical coherence tomography,” Science 254, 1178–1181 (1991).
[Crossref]

Chen, N.

Chen, S.

Chen, Z.

Costa, M. A.

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

Cox, I.

C. Sheppard, D. Hamilton, and I. Cox, “Optical microscopy with extended depth of field,” Proc. R. Soc. London Ser. A 387, 171–186 (1983).
[Crossref]

Cui, D.

de Boer, J. F.

de Groot, M.

Ding, Z.

Ferrara, D.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Flotte, T.

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

Fujimoto, J. G.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Gan, X.

Gardecki, J. A.

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Gregory, K.

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

Grulkowski, I.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Gu, M.

Guagliumi, G.

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

Hamilton, D.

C. Sheppard, D. Hamilton, and I. Cox, “Optical microscopy with extended depth of field,” Proc. R. Soc. London Ser. A 387, 171–186 (1983).
[Crossref]

Hee, M. R.

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

Hornegger, J.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Howe, W. C.

Huang, D.

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

Kraus, M. F.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Lasser, T.

Lee, K.-S.

Leitgeb, R.

Lin, C. P.

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

Liu, C.

Liu, J. J.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Liu, L.

E. Bo and L. Liu, “Spectral domain optical coherence tomography with extended depth-of-focus by aperture synthesis,” Proc. SPIE 10024, 1002451 (2016).
[Crossref]

X. Liu, S. Chen, D. Cui, X. Yu, and L. Liu, “Spectral estimation optical coherence tomography for axial super-resolution,” Opt. Express 23, 26521–26532 (2015).
[Crossref]

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

L. Liu, C. Liu, W. C. Howe, C. Sheppard, and N. Chen, “Binary-phase spatial filter for real-time swept-source optical coherence microscopy,” Opt. Lett. 32, 2375–2377 (2007).
[Crossref]

Liu, X.

Mao, X.

Marks, D. L.

T. S. Ralston, D. L. Marks, P. S. Carney, and S. A. Boppart, “Interferometric synthetic aperture microscopy,” Nat. Phys. 3, 129–134 (2007).
[Crossref]

Mo, J.

Mohler, K. J.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Nadkarni, S. K.

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Nelson, J. S.

Puliafito, C. A.

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

Ralston, T. S.

T. S. Ralston, D. L. Marks, P. S. Carney, and S. A. Boppart, “Interferometric synthetic aperture microscopy,” Nat. Phys. 3, 129–134 (2007).
[Crossref]

Ren, H.

Rolland, J. P.

Rollins, A. M.

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

Schuman, J. S.

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

Sheppard, C.

Simon, D. I.

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

Steinmann, L.

Stinson, W. G.

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

Swanson, E. A.

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

Tearney, G. J.

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Toussaint, J. D.

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Villiger, M.

Waheed, N.

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Wilson, T.

Yagi, Y.

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Yu, X.

Zhao, Y.

J. Opt. Soc. Am. A (4)

JACC Cardiovasc Interv. (1)

H. G. Bezerra, M. A. Costa, G. Guagliumi, A. M. Rollins, and D. I. Simon, “Intracoronary optical coherence tomography: a comprehensive review: clinical and research applications,” JACC Cardiovasc Interv. 2, 1035–1046 (2009).
[Crossref]

Nat. Med. (1)

L. Liu, J. A. Gardecki, S. K. Nadkarni, J. D. Toussaint, Y. Yagi, B. E. Bouma, and G. J. Tearney, “Imaging the subcellular structure of human coronary atherosclerosis using micro-optical coherence tomography,” Nat. Med. 17, 1010–1014 (2011).
[Crossref]

Nat. Phys. (1)

T. S. Ralston, D. L. Marks, P. S. Carney, and S. A. Boppart, “Interferometric synthetic aperture microscopy,” Nat. Phys. 3, 129–134 (2007).
[Crossref]

Ophthalmology (1)

D. Ferrara, K. J. Mohler, N. Waheed, M. Adhi, J. J. Liu, I. Grulkowski, M. F. Kraus, C. Baumal, J. Hornegger, and J. G. Fujimoto, “En face enhanced-depth swept-source optical coherence tomography features of chronic central serous chorioretinopathy,” Ophthalmology 121, 719–726 (2014).
[Crossref]

Opt. Express (2)

Opt. Lett. (5)

Proc. R. Soc. London Ser. A (1)

C. Sheppard, D. Hamilton, and I. Cox, “Optical microscopy with extended depth of field,” Proc. R. Soc. London Ser. A 387, 171–186 (1983).
[Crossref]

Proc. SPIE (1)

E. Bo and L. Liu, “Spectral domain optical coherence tomography with extended depth-of-focus by aperture synthesis,” Proc. SPIE 10024, 1002451 (2016).
[Crossref]

Science (1)

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

Other (1)

M. Gu, Principles of Three-Dimensional Imaging in Confocal Microscopes (World Scientific, 1996).

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Figures (5)

Fig. 1.
Fig. 1. Working principles of multiple aperture synthesis. (a) Schematic with a microcylindrical lens centered at the fiber pinhole. (b) Schematic with a microcylindrical lens (MCL) transversely shifted by a step size of ΔL. (a′)–(b′) Magnified views of the optical beam indicated by the dashed boxes in (a)–(b). (c) Five apertures generated by the transversely shifted microcylindrical lens and the aperture of the objective lens. (d) Focusing beams of the five apertures in (c). (e) Optical axes of the focusing beams of the five apertures in (c). SMF, single-mode fiber; MCL, microcylindrical lens; PZT, piezoelectric transducer; L1, collimating lens; L2, focusing lens; LF, low spatial frequency; and HF, high spatial frequency. Δz is the total optical path difference between A-lines acquired in (a) and (b), and composed of two components: Δzs induced by the transverse shift of the MCL and the defocusing term Δzc. ΔL is the transverse shifting step size of the microcylindrical lens.
Fig. 2.
Fig. 2. Numerical simulation results. (a)–(c) PFs of a full aperture, an annular apodized aperture and an MAS. (d)–(f) Two-dimensional (2D) coherent transfer functions (CTFs) of a full aperture, an annular apodized aperture, and an MAS in the focal plane as a function over the transverse (m and n) spatial frequencies. (g)–(i) 2D CTFs of a full aperture, an annular apodized aperture, and an MAS as a function over the transverse spatial frequency (m) and axial (z) dimensions. (j)–(l) 2D PSFs of a full aperture, an apodization, and an MAS as a function over the transverse (x) and axial (z) dimensions. (mn) Transverse CTFs in the focal plane and at an out-of-focus plane of z=b, respectively. b is the confocal parameter. (o)–(p) Transverse PSFs in the focal plane at an out-of-focus plane of z=b and 10b. Intensities in all figures are normalized by their maximum values.
Fig. 3.
Fig. 3. Schematic of the MAS SD-OCT system. SLD, superluminescent diode; OC1-2, 9010 fiber-optic coupler; L1, L3, L5, and L6, collimating lens; L2 and L4, focusing lens; L7, camera lens; NDF, neutral density filter; RM, reference mirror; MCL, microcylindrical lens; PZT, piezoelectric transducer; BS, beam splitter; GS, galvo scanner; G, transmission diffraction grating; IMAQ, image acquisition; C, computer; and PC, polarization controller.
Fig. 4.
Fig. 4. PZT assembly and adjustment. (a) PZT is mounted on a two-axis goniometer stacked on a three-axis compact stage. Inset: Magnified view shows that two MCLs are cured on the silica base. (b) Cross-sectional width of the microcylindrical lens. (c) Alignment of the MCL and the tip of the sample fiber.
Fig. 5.
Fig. 5. Stepwise image sequence in linear scale: (a) Dispersion-compensated B-scan from one of five apertures; (b) Resulting B-scan of the axial-shift operation, which is the first step of the MAS; (c) Resulting B-scan of the defocusing correction operation, which is the second step of the MAS. (a′)–(c′) Magnified view of two calibration beads indicated by the dashed black boxes in (a)–(c). (d) Transverse FWHMs of 50 calibration beads at variable depths.

Equations (8)

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

I(k)=S(k)[DC+2Ir(k)Is(k)cos(2kz)dz+AC],
In(k)=Ir(k)Is(k)[exp(i2kzn)+C.C.],
In(k)=exp(iαn)·Ir(k)Is(k)[exp(i2kzn)exp(iβn)],
Inax(k)=In(k)·exp(iαn),
Inde(k)=Inax(k)·exp(iβn),
Ire=n=1mIn(k)·exp[iαnop(z)]·exp[iβnop(z)].
C(m,n)=p(fλm,fλn)p(fλm,fλn),
F(x,y)=C(m,n)exp[2πi(mx+ny)]dmdn,

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