Abstract

Multi-exposure laser speckle contrast imaging (MELSCI) systems based on high frame rate cameras are suitable for wide-field quantitative measurement of blood flow. However, high-speed camera–based MELSCI requires high power consumption, large memory, and high processing capability, which may lead to relatively large and expensive hardware. To realize a compact and cost-efficient MELSCI system, we discuss an application of the multi-tap CMOS image sensor originally designed for time-of-flight range imaging. This image sensor operated in the global shutter mode and every pixel was provided with multiple charge-storage diodes. Multiple images for different exposures were acquired simultaneously because exposure patterns were programmable to implement an arbitrary exposure duration for each tap. The frame rate was close to video frame rates (30 frames per second (fps)) regardless of the exposure pattern. The feasibility of the proposed method was verified by simulations that were performed with real speckle images captured by a high-speed camera at 40 kfps. Experiments with a four-tap CMOS image sensor demonstrated that a flow speed map was obtained at a moderate frame rate such as 35 fps for a moving ground glass plate and 45 fps for flowing Intralipose, which were linearly moved at speeds of 1–5 mm/s.

© 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Full Article  |  PDF Article
OSA Recommended Articles
Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array

Shen Sun, Barrie R. Hayes-Gill, Diwei He, Yiqun Zhu, and Stephen P. Morgan
Opt. Lett. 40(20) 4587-4590 (2015)

High-speed multi-exposure laser speckle contrast imaging with a single-photon counting camera

Tanja Dragojević, Danilo Bronzi, Hari M. Varma, Claudia P. Valdes, Clara Castellvi, Federica Villa, Alberto Tosi, Carles Justicia, Franco Zappa, and Turgut Durduran
Biomed. Opt. Express 6(8) 2865-2876 (2015)

CMOS computational camera with a two-tap coded exposure image sensor for single-shot spatial-temporal compressive sensing

Yi Luo, Jacky Jiang, Mengye Cai, and Shahriar Mirabbasi
Opt. Express 27(22) 31475-31489 (2019)

References

  • View by:
  • |
  • |
  • |

  1. J. D. Briers, “Laser speckle contrast analysis (LASCA): a nonscanning, full-field technique for monitoring capillary blood flow,” J. Biomed. Opt. 1(2), 174 (1996).
    [Crossref]
  2. W. J. Tom, X. Zhang, A. Gopal, A. B. Parthasarathy, and A. K. Dunn, “Robust flow measurement with multi-exposure speckle imaging,” Opt. Express 16(3), 1975 (2008).
    [Crossref]
  3. P. Zakharov, A. C. Völker, M. T. Wyss, F. Haiss, N. Calcinaghi, C. Zunzunegui, A. Buck, F. Scheffold, and B. Weber, “Dynamic laser speckle imaging of cerebral blood flow,” Opt. Express 17(16), 13904–17 (2009).
    [Crossref]
  4. K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
    [Crossref]
  5. M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
    [Crossref]
  6. C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
    [Crossref]
  7. M. Nagahara, Y. Tamaki, M. Araie, and H. Fujii, “Real-Time Blood Velocity Measurements in Human Retinal,” Jpn. J. Ophthalmol.5155(99), (1998).
  8. A. B. Parthasarathy, S. M. S. Kazmi, and A. K. Dunn, “Quantitative imaging of ischemic stroke through thinned skull in mice with Multi Exposure Speckle Imaging,” Biomed. Opt. Express 1(1), 246 (2010).
    [Crossref]
  9. S. M. S. Kazmi, A. B. Parthasarthy, N. E. Song, T. A. Jones, and A. K. Dunn, “Chronic imaging of cortical blood flow using Multi-Exposure Speckle Imaging,” J. Cereb. Blood Flow Metab. 33(6), 798–808 (2013).
    [Crossref]
  10. A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
    [Crossref]
  11. F. Zappa, T. Durduran, A. Tosi, C. Justicia, F. Villa, D. Bronzi, H. M. Varma, C. P. Valdes, T. Dragojević, and C. Castellvi, “High-speed multi-exposure laser speckle contrast imaging with a single-photon counting camera,” Biomed. Opt. Express 6(8), 2865 (2015).
    [Crossref]
  12. S. Sun, Y. Zhu, S. P. Morgan, D. He, and B. R. Hayes-Gill, “Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array,” Opt. Lett. 40(20), 4587 (2015).
    [Crossref]
  13. S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
    [Crossref]
  14. M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
    [Crossref]
  15. S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
    [Crossref]
  16. C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).
  17. T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
    [Crossref]
  18. G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
    [Crossref]
  19. G. Wan, “Applications of Multi-Bucket Sensors to Computational Photography,” Stanford CG Lab Tech. Rep.1–9 (2012).
  20. M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
    [Crossref]
  21. M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
    [Crossref]
  22. G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
    [Crossref]
  23. R. K. Jain, L. L. Munn, and D. Fukumura, “Dissecting tumour pathophysiology using intravital microscopy,” Nat. Rev. Cancer 2(4), 266–276 (2002).
    [Crossref]
  24. H. Cheng and T. Q. Duong, “Simplified laser-speckle-imaging analysis method and its application to retinal blood flow imaging,” Opt. Lett. 32(15), 2188–2190 (2007).
    [Crossref]
  25. B. Choi, J. C. Ramirez-San-Juan, J. Lotfi, and J. Stuart Nelson, “Linear response range characterization and in vivo application of laser speckle imaging of blood flow dynamics,” J. Biomed. Opt. 11(4), 041129 (2006).
    [Crossref]
  26. S. M. S. Kazmi, E. Faraji, M. A. Davis, Y.-Y. Huang, X. J. Zhang, and A. K. Dunn, “Flux or speed? Examining speckle contrast imaging of vascular flows,” Biomed. Opt. Express 6(7), 2588 (2015).
    [Crossref]
  27. D. D. Duncan and S. J. Kirkpatrick, “Can laser speckle flowmetry be made a quantitative tool?” J. Opt. Soc. Am. A 25(8), 2088 (2008).
    [Crossref]
  28. K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).
  29. A. Fuentes-Garcia, J. C. Ramirez-San-Juan, N. Salazar-Hermenegildo, B. Choi, R. Ramos-Garcia, and E. Mendez-Aguilar, “Effects of speckle/pixel size ratio on temporal and spatial speckle-contrast analysis of dynamic scattering systems: Implications for measurements of blood-flow dynamics,” Biomed. Opt. Express 4(10), 1883 (2013).
    [Crossref]
  30. L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
    [Crossref]
  31. M. Chen, X. Chen, P. Li, D. Wen, Y. Wang, Q. Huang, and J. Lu, “Improving the estimation of flow speed for laser speckle imaging with single exposure time,” Opt. Lett. 42(1), 57 (2017).
    [Crossref]
  32. S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

2018 (2)

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

2017 (2)

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

M. Chen, X. Chen, P. Li, D. Wen, Y. Wang, Q. Huang, and J. Lu, “Improving the estimation of flow speed for laser speckle imaging with single exposure time,” Opt. Lett. 42(1), 57 (2017).
[Crossref]

2016 (3)

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

2015 (4)

2013 (2)

2012 (1)

G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
[Crossref]

2011 (1)

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

2010 (1)

2009 (2)

M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
[Crossref]

P. Zakharov, A. C. Völker, M. T. Wyss, F. Haiss, N. Calcinaghi, C. Zunzunegui, A. Buck, F. Scheffold, and B. Weber, “Dynamic laser speckle imaging of cerebral blood flow,” Opt. Express 17(16), 13904–17 (2009).
[Crossref]

2008 (2)

2007 (1)

2006 (1)

B. Choi, J. C. Ramirez-San-Juan, J. Lotfi, and J. Stuart Nelson, “Linear response range characterization and in vivo application of laser speckle imaging of blood flow dynamics,” J. Biomed. Opt. 11(4), 041129 (2006).
[Crossref]

2005 (1)

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

2004 (1)

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

2003 (1)

G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
[Crossref]

2002 (1)

R. K. Jain, L. L. Munn, and D. Fukumura, “Dissecting tumour pathophysiology using intravital microscopy,” Nat. Rev. Cancer 2(4), 266–276 (2002).
[Crossref]

1996 (1)

J. D. Briers, “Laser speckle contrast analysis (LASCA): a nonscanning, full-field technique for monitoring capillary blood flow,” J. Biomed. Opt. 1(2), 174 (1996).
[Crossref]

Acharya, S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Adepu, P.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Agi, I.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Agranov, G.

G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
[Crossref]

Ahmed, M.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Akkaya, O.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Ali, G.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Alvandpour, A.

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

Aoyama, S.

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Araie, M.

M. Nagahara, Y. Tamaki, M. Araie, and H. Fujii, “Real-Time Blood Velocity Measurements in Human Retinal,” Jpn. J. Ophthalmol.5155(99), (1998).

Bamji, C. S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Bray, R. C.

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

Briers, J. D.

J. D. Briers, “Laser speckle contrast analysis (LASCA): a nonscanning, full-field technique for monitoring capillary blood flow,” J. Biomed. Opt. 1(2), 174 (1996).
[Crossref]

Bronzi, D.

Buck, A.

Calcinaghi, N.

Castellvi, C.

Chan, V. H.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Chen, M.

Chen, X.

Cheng, H.

Choi, B.

Davis, M. A.

Dozier, S. S.

G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
[Crossref]

Dragojevic, T.

Draijer, M.

M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
[Crossref]

Duncan, D. D.

Dunn, A. K.

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

S. M. S. Kazmi, E. Faraji, M. A. Davis, Y.-Y. Huang, X. J. Zhang, and A. K. Dunn, “Flux or speed? Examining speckle contrast imaging of vascular flows,” Biomed. Opt. Express 6(7), 2588 (2015).
[Crossref]

S. M. S. Kazmi, A. B. Parthasarthy, N. E. Song, T. A. Jones, and A. K. Dunn, “Chronic imaging of cortical blood flow using Multi-Exposure Speckle Imaging,” J. Cereb. Blood Flow Metab. 33(6), 798–808 (2013).
[Crossref]

A. B. Parthasarathy, S. M. S. Kazmi, and A. K. Dunn, “Quantitative imaging of ischemic stroke through thinned skull in mice with Multi Exposure Speckle Imaging,” Biomed. Opt. Express 1(1), 246 (2010).
[Crossref]

W. J. Tom, X. Zhang, A. Gopal, A. B. Parthasarathy, and A. K. Dunn, “Robust flow measurement with multi-exposure speckle imaging,” Opt. Express 16(3), 1975 (2008).
[Crossref]

Duong, T. Q.

Durduran, T.

Elkhatib, T.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Faraji, E.

Fenton, M.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Forrester, K. R.

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

Fox, D. J.

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

Frank, R.

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

Fredriksson, I.

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

Fuentes-Garcia, A.

Fujii, H.

M. Nagahara, Y. Tamaki, M. Araie, and H. Fujii, “Real-Time Blood Velocity Measurements in Human Retinal,” Jpn. J. Ophthalmol.5155(99), (1998).

Fukumura, D.

R. K. Jain, L. L. Munn, and D. Fukumura, “Dissecting tumour pathophysiology using intravital microscopy,” Nat. Rev. Cancer 2(4), 266–276 (2002).
[Crossref]

Gampell, D.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Godbaz, J.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Gopal, A.

Haiss, F.

Halin, I. A.

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

Han, S. M.

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

Han, S.-M.

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

Handa, Y.

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Hayes-Gill, B. R.

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

S. Sun, Y. Zhu, S. P. Morgan, D. He, and B. R. Hayes-Gill, “Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array,” Opt. Lett. 40(20), 4587 (2015).
[Crossref]

He, D.

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

S. Sun, Y. Zhu, S. P. Morgan, D. He, and B. R. Hayes-Gill, “Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array,” Opt. Lett. 40(20), 4587 (2015).
[Crossref]

Hondebrink, E.

M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
[Crossref]

Huang, Q.

Huang, Y.-Y.

Hultman, M.

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

Huynh, N. T.

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

Jain, R. K.

R. K. Jain, L. L. Munn, and D. Fukumura, “Dissecting tumour pathophysiology using intravital microscopy,” Nat. Rev. Cancer 2(4), 266–276 (2002).
[Crossref]

Jones, T. A.

S. M. S. Kazmi, A. B. Parthasarthy, N. E. Song, T. A. Jones, and A. K. Dunn, “Chronic imaging of cortical blood flow using Multi-Exposure Speckle Imaging,” J. Cereb. Blood Flow Metab. 33(6), 798–808 (2013).
[Crossref]

Justicia, C.

Kagawa, K.

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

Kasugai, T.

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

Kawahito, S.

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Kawata, Y.

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

Kazmi, S. M. S.

Kazmi, S. S.

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

Kirkpatrick, S. J.

Komazawa, A.

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Kondo, K.

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Kordus, L.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Larsson, M.

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

Leonard, C.

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

Li, P.

Li, X.

G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
[Crossref]

Li, Z.

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

Lindsay, R.

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

Lotfi, J.

B. Choi, J. C. Ramirez-San-Juan, J. Lotfi, and J. Stuart Nelson, “Linear response range characterization and in vivo application of laser speckle imaging of blood flow dynamics,” J. Biomed. Opt. 11(4), 041129 (2006).
[Crossref]

Lu, J.

McCarthy, S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

McCauley, R.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Mehta, S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Member, G. S.

G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
[Crossref]

Mendez-Aguilar, E.

Michiba, T.

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Mogallapu, V.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Morgan, S. P.

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

S. Sun, Y. Zhu, S. P. Morgan, D. He, and B. R. Hayes-Gill, “Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array,” Opt. Lett. 40(20), 4587 (2015).
[Crossref]

Mukadam, M.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Mukherjee, A.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Munn, L. L.

R. K. Jain, L. L. Munn, and D. Fukumura, “Dissecting tumour pathophysiology using intravital microscopy,” Nat. Rev. Cancer 2(4), 266–276 (2002).
[Crossref]

Murari, K.

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

Nagahara, M.

M. Nagahara, Y. Tamaki, M. Araie, and H. Fujii, “Real-Time Blood Velocity Measurements in Human Retinal,” Jpn. J. Ophthalmol.5155(99), (1998).

Nagaraja, S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Nayak, S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

O’Connor, P.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Okura, Y.

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Olin, K. E.

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

Parthasarathy, A. B.

Parthasarthy, A. B.

S. M. S. Kazmi, A. B. Parthasarthy, N. E. Song, T. A. Jones, and A. K. Dunn, “Chronic imaging of cortical blood flow using Multi-Exposure Speckle Imaging,” J. Cereb. Blood Flow Metab. 33(6), 798–808 (2013).
[Crossref]

Pathak, A. P.

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

Payne, A.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Perry, T.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Prather, L.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Qian, W.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Rajasekaran, V.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Ramirez-San-Juan, J. C.

Ramos-Garcia, R.

Readinger, A.

G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
[Crossref]

Rege, A.

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

Richards, L. M.

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

Salazar-Hermenegildo, N.

Scheffold, F.

Seifert, A.

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

Seo, M. W.

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

Seo, M.-W.

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

Shirakawa, Y.

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

Snow, D.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Song, N. E.

S. M. S. Kazmi, A. B. Parthasarthy, N. E. Song, T. A. Jones, and A. K. Dunn, “Chronic imaging of cortical blood flow using Multi-Exposure Speckle Imaging,” J. Cereb. Blood Flow Metab. 33(6), 798–808 (2013).
[Crossref]

Steenbergen, W.

M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
[Crossref]

Stewart, C.

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

Stewart, C. J.

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

Strömberg, T.

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

Stuart Nelson, J.

B. Choi, J. C. Ramirez-San-Juan, J. Lotfi, and J. Stuart Nelson, “Linear response range characterization and in vivo application of laser speckle imaging of blood flow dynamics,” J. Biomed. Opt. 11(4), 041129 (2006).
[Crossref]

Sun, S.

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

S. Sun, Y. Zhu, S. P. Morgan, D. He, and B. R. Hayes-Gill, “Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array,” Opt. Lett. 40(20), 4587 (2015).
[Crossref]

Takasawa, T.

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

Tamaki, Y.

M. Nagahara, Y. Tamaki, M. Araie, and H. Fujii, “Real-Time Blood Velocity Measurements in Human Retinal,” Jpn. J. Ophthalmol.5155(99), (1998).

Teranishi, N.

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

Thakor, N. V.

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

Thompson, B.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Tom, W. J.

Tosi, A.

Trang, H.

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

Tulip, J.

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

Valdes, C. P.

Van Leeuwen, T.

M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
[Crossref]

Vargas, G.

G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
[Crossref]

Varma, H. M.

Villa, F.

Völker, A. C.

Waldron, J. S.

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

Wan, G.

G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
[Crossref]

G. Wan, “Applications of Multi-Bucket Sensors to Computational Photography,” Stanford CG Lab Tech. Rep.1–9 (2012).

Wang, Y.

Weber, B.

Welch, A. J.

G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
[Crossref]

Wen, D.

Wurster, S.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Wyss, M. T.

Xu, Z.

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

Yamada, K.

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

Yasutomi, K.

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

Zakharov, P.

Zappa, F.

Zhang, X.

Zhang, X. J.

Zhu, Y.

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

S. Sun, Y. Zhu, S. P. Morgan, D. He, and B. R. Hayes-Gill, “Multi-exposure laser speckle contrast imaging using a high frame rate CMOS sensor with a field programmable gate array,” Opt. Lett. 40(20), 4587 (2015).
[Crossref]

Zunzunegui, C.

Biomed. Opt. Express (4)

Burns (1)

C. J. Stewart, R. Frank, K. R. Forrester, J. Tulip, R. Lindsay, and R. C. Bray, “A comparison of two laser-based methods for determination of burn scar perfusion: Laser Doppler versus laser speckle imaging,” Burns 31(6), 744–752 (2005).
[Crossref]

Electron. Imaging (1)

T. Takasawa, K. Kagawa, S.-M. Han, H. Trang, S. Kawahito, K. Yasutomi, S. Aoyama, and T. Kasugai, “A Time-of-Flight CMOS Range Image Sensor Using 4-Tap Output Pixels with Lateral-Electric-Field Control,” Electron. Imaging 2016(12), 1–6 (2016).
[Crossref]

IEEE J. Electron Devices Soc. (1)

S. M. Han, T. Takasawa, K. Yasutomi, S. Aoyama, K. Kagawa, and S. Kawahito, “A time-of-flight range image sensor with background canceling lock-in pixels based on lateral electric field charge modulation,” IEEE J. Electron Devices Soc. 3(3), 267–275 (2015).
[Crossref]

IEEE J. Solid-State Circuits (3)

G. Wan, G. S. Member, X. Li, and G. Agranov, “CMOS Image Sensors With Multi-Bucket Pixels for Solid-State Circuits,” IEEE J. Solid-State Circuits 47(4), 1031–1042 (2012).
[Crossref]

M. W. Seo, K. Kagawa, K. Yasutomi, Y. Kawata, N. Teranishi, Z. Li, I. A. Halin, and S. Kawahito, “A 10 ps time-resolution CMOS image sensor with two-tap true-CDS lock-in pixels for fluorescence lifetime imaging,” IEEE J. Solid-State Circuits 51(1), 141–154 (2016).
[Crossref]

M. W. Seo, Y. Shirakawa, Y. Kawata, K. Kagawa, K. Yasutomi, and S. Kawahito, “A time-resolved four-tap lock-in pixel CMOS image sensor for real-time fluorescence lifetime imaging microscopy,” IEEE J. Solid-State Circuits 53(8), 2319–2330 (2018).
[Crossref]

IEEE Trans. Biomed. Eng. (1)

K. R. Forrester, J. Tulip, C. Leonard, C. Stewart, and R. C. Bray, “A laser speckle imaging technique for measuring tissue perfusion,” IEEE Trans. Biomed. Eng. 51(11), 2074–2084 (2004).
[Crossref]

J. Biomed. Opt. (3)

J. D. Briers, “Laser speckle contrast analysis (LASCA): a nonscanning, full-field technique for monitoring capillary blood flow,” J. Biomed. Opt. 1(2), 174 (1996).
[Crossref]

A. P. Pathak, A. Seifert, N. V. Thakor, A. Rege, and K. Murari, “Multiexposure laser speckle contrast imaging of the angiogenic microenvironment,” J. Biomed. Opt. 16(5), 056006 (2011).
[Crossref]

B. Choi, J. C. Ramirez-San-Juan, J. Lotfi, and J. Stuart Nelson, “Linear response range characterization and in vivo application of laser speckle imaging of blood flow dynamics,” J. Biomed. Opt. 11(4), 041129 (2006).
[Crossref]

J. Biophotonics (1)

M. Hultman, I. Fredriksson, M. Larsson, A. Alvandpour, and T. Strömberg, “A 15.6 frames per second 1-megapixel multiple exposure laser speckle contrast imaging setup,” J. Biophotonics 11(2), e201700069–9 (2018).
[Crossref]

J. Cereb. Blood Flow Metab. (2)

L. M. Richards, S. S. Kazmi, K. E. Olin, J. S. Waldron, D. J. Fox, and A. K. Dunn, “Intraoperative multi-exposure speckle imaging of cerebral blood flow,” J. Cereb. Blood Flow Metab. 37(9), 3097–3109 (2017).
[Crossref]

S. M. S. Kazmi, A. B. Parthasarthy, N. E. Song, T. A. Jones, and A. K. Dunn, “Chronic imaging of cortical blood flow using Multi-Exposure Speckle Imaging,” J. Cereb. Blood Flow Metab. 33(6), 798–808 (2013).
[Crossref]

J. Opt. Soc. Am. A (1)

Lasers Med. Sci. (1)

M. Draijer, E. Hondebrink, T. Van Leeuwen, and W. Steenbergen, “Review of laser speckle contrast techniques for visualizing tissue perfusion,” Lasers Med. Sci. 24(4), 639–651 (2009).
[Crossref]

Nat. Rev. Cancer (1)

R. K. Jain, L. L. Munn, and D. Fukumura, “Dissecting tumour pathophysiology using intravital microscopy,” Nat. Rev. Cancer 2(4), 266–276 (2002).
[Crossref]

Opt. Express (2)

Opt. Lasers Eng. (1)

S. Sun, B. R. Hayes-Gill, D. He, Y. Zhu, N. T. Huynh, and S. P. Morgan, “Comparison of laser Doppler and laser speckle contrast imaging using a concurrent processing system,” Opt. Lasers Eng. 83, 1–9 (2016).
[Crossref]

Opt. Lett. (3)

Photochem. Photobiol. (1)

G. Vargas, A. Readinger, S. S. Dozier, and A. J. Welch, “Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography,” Photochem. Photobiol. 77(5), 541 (2003).
[Crossref]

Other (5)

K. Kondo, K. Yasutomi, K. Yamada, A. Komazawa, Y. Handa, Y. Okura, T. Michiba, S. Aoyama, and S. Kawahito, “A Built-in Drift-field PD Based 4-tap Lock-in Pixel for Time-of-Flight CMOS Range Image Sensors,” 5–6 (n.d.).

S. Kawahito, K. Yasutomi, M.-W. Seo, K. Kagawa, Y. Shirakawa, and N. Teranishi, “Design of an 8-tap CMOS lock-in pixel with lateral electric field charge modulator for highly time-resolved imaging,” Proc. SPIE10108(1), 101080N (2017).

G. Wan, “Applications of Multi-Bucket Sensors to Computational Photography,” Stanford CG Lab Tech. Rep.1–9 (2012).

C. S. Bamji, S. Mehta, B. Thompson, T. Elkhatib, S. Wurster, O. Akkaya, A. Payne, J. Godbaz, M. Fenton, V. Rajasekaran, L. Prather, S. Nagaraja, V. Mogallapu, D. Snow, R. McCauley, M. Mukadam, I. Agi, S. McCarthy, Z. Xu, T. Perry, W. Qian, V. H. Chan, P. Adepu, G. Ali, M. Ahmed, A. Mukherjee, S. Nayak, D. Gampell, S. Acharya, L. Kordus, and P. O’Connor, “IMpixel 65 nm BSI 320 MHz demodulated TOF Image sensor with 3µm global shutter pixels and analog binning,” Dig. Tech. Pap. - IEEE Int. Solid-State Circuits Conf.61, 94–96 (2018).

M. Nagahara, Y. Tamaki, M. Araie, and H. Fujii, “Real-Time Blood Velocity Measurements in Human Retinal,” Jpn. J. Ophthalmol.5155(99), (1998).

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (12)

Fig. 1.
Fig. 1. An example of 4-tap charge modulation pixel: (a) layout, (b) schematic diagram, and (c) operation timing chart. FD: floating diffusion. G: gate. GD: gate to drain charges.
Fig. 2.
Fig. 2. (a) Equal exposure pattern for better SNR by averaging. (b) Exponential exposure pattern to extend the measurable flow speed range.
Fig. 3.
Fig. 3. Experimental setup (a) Schematic of the experimental setup (b) Ground glass setup (c) Intralipose setup
Fig. 4.
Fig. 4. Data processing of high-speed camera images. The squared contrast value, K2, for each exposure time was calculated for each data set. K2 and speed were obtained by further averaging of the 19 data sets.
Fig. 5.
Fig. 5. Measured K2 and fitted curves by Eq. (1): (a) Ground glass and (b) Intralipose. K2 was normalized by K2 = 0.0570 of the static ground glass plate at the exposure time of 25 μs. Total number of exposure time was 13.
Fig. 6.
Fig. 6. Simulated K2 curves of the ground glass with the equal exposure. K2 was normalized by K2 = 0.0570 given by the static ground glass plate at the exposure time of 25µs. The unit exposure time, T0: (a) 0.2 ms, (b) 1.6 ms, (c) 3.2 ms, and (d) 6.4 ms.
Fig. 7.
Fig. 7. Simulated K2 curves of the ground glass with the exponential exposure. K2 was normalized by K2 = 0.0570 given by the static ground glass plate at the exposure time of 25µs. The unit exposure time, T0: (a) 0.2 ms, (b) 0.8 ms, (c) 1.6 ms, and (d) 3.2 ms.
Fig. 8.
Fig. 8. Normalized estimated speed vs. actual speed. (a)(b) High-speed camera. Measured object: (a)(c)(e) Ground glass, (b)(d)(f) Intralipose. Exposure pattern: (c)(d) equal exposure pattern. Exposure pattern: (e)(f) exponential exposure pattern. Error bars are shown for optimal T0 alone. Error bars of other T0’s are omitted for clarity.
Fig. 9.
Fig. 9. Mean FNR vs. T0 (ms). Exposure pattern: (a)(b) Equal exposure pattern. Exposure pattern: (c)(d) Exponential exposure pattern. Measured object: (a)(c) Ground glass plate, (b)(d) Intralipose.
Fig. 10.
Fig. 10. Timing chart of the four-tap CMOS image sensor
Fig. 11.
Fig. 11. Measured K2 and fitted curves for (a) ground glass and (c) Intralipose. Normalized measured speed vs actual speed for (b) ground glass and (d) Intralipose. K2 was normalized by K2 = 0.1709 given by the static ground glass plate at the exposure time of 6.4ms.
Fig. 12.
Fig. 12. Speed maps measured by the four-tap CMOS image sensor for (a) ground glass and (b) Intralipose at different flow speeds. The estimated speed was calibrated. (c) An example of a captured raw image for the Intralipose. The flow speed maps were obtained from a single frame. No averaging was performed.

Tables (4)

Tables Icon

Table 1. Specifications of the cameras

Tables Icon

Table 2. Flow speed to noise ratios for high-speed camera, equal and exponential exposure patterns

Tables Icon

Table 3. Relative estimation error for high-speed camera, equal and exponential exposure patterns

Tables Icon

Table 4. Flow speed to noise ratios for equal and exponential exposure patterns with 4-tap sensor

Equations (6)

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

K ( T ) = ( I I ) 2 I 2 = β ρ 2 e 2 x 1 + 2 x 2 x 2 + 4 β ρ ( 1 ρ ) e x 1 + x x 2 + v n e + v n
x = T/ τ c
v = λ / ( 2 π τ c )
I i ( x , y ) = n = 0 N 1 I ( x , y ; n T min ) G i ( n T min ) ,
V M E L S C I = γ × 1 τ c + δ ,
V C A L = λ 2 π γ ( V M E L S C I δ )

Metrics