Abstract

In thermal light ghost imaging, the transparent mask, located in the object arm of the optical setup, is numerically reconstructed by correlating the speckle patterns acquired by the video camera with the output of a bucket detector placed behind the mask. We show that the visibility of images can be significantly improved by discarding every speckle pattern whose bucket output falls below a certain threshold. We also demonstrate that the efficiency of the conventional method strongly decreases when the speckle statistics deviate from the negative exponential, whereas the threshold method is more robust against changes in the statistical distribution of the speckle intensity. We also provide reasonable statistical explanations for these results.

© 2007 Optical Society of America

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  1. A. V. Belinski and D. N. Klyshko, "Two-photon optics: diffraction, holography, and transformation of two-dimensional signals," J. Exp. Theor. Phys. 78, 259-262 (1994).
  2. T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
    [CrossRef] [PubMed]
  3. J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
    [CrossRef] [PubMed]
  4. R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Two-photon coincidence imaging with a classical source," Phys. Rev. Lett. 89, 113601 (2002).
    [CrossRef] [PubMed]
  5. A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
    [CrossRef] [PubMed]
  6. F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
    [CrossRef] [PubMed]
  7. A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
    [CrossRef] [PubMed]
  8. M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
    [CrossRef] [PubMed]
  9. R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Quantum and classical coincidence imaging," Phys. Rev. Lett. 92, 033601 (2004).
    [CrossRef] [PubMed]
  10. J. Cheng and S. Han, "Incoherent coincidence imaging and its applicability in x-ray diffraction," Phys. Rev. Lett. 92, 093903 (2004).
    [CrossRef] [PubMed]
  11. M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
    [CrossRef]
  12. L. Basano and P. Ottonello, "Ghost-imaging: open secrets and puzzles for undergraduates," Am. J. Phys. 75, 343-351 (2007).
    [CrossRef]
  13. G. Scarcelli, V. Berardi, and Y. Shih, "Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations?" Phys. Rev. Lett. 96, 063602 (2006).
    [CrossRef] [PubMed]
  14. G. Scarcelli, V. Berardi, and Y. Shih, "Phase-conjugate mirror via two-photon thermal light imaging," Appl. Phys. Lett. 88, 061106 (2006).
    [CrossRef]
  15. J. W. Goodman, "Statistical properties of leaser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), pp. 46-54.
  16. J. W. Goodman, "Statistical properties of laser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), p. 53, Eq. 2.130.
    [CrossRef]

2007

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

L. Basano and P. Ottonello, "Ghost-imaging: open secrets and puzzles for undergraduates," Am. J. Phys. 75, 343-351 (2007).
[CrossRef]

2006

G. Scarcelli, V. Berardi, and Y. Shih, "Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations?" Phys. Rev. Lett. 96, 063602 (2006).
[CrossRef] [PubMed]

G. Scarcelli, V. Berardi, and Y. Shih, "Phase-conjugate mirror via two-photon thermal light imaging," Appl. Phys. Lett. 88, 061106 (2006).
[CrossRef]

2005

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
[CrossRef] [PubMed]

2004

M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Quantum and classical coincidence imaging," Phys. Rev. Lett. 92, 033601 (2004).
[CrossRef] [PubMed]

J. Cheng and S. Han, "Incoherent coincidence imaging and its applicability in x-ray diffraction," Phys. Rev. Lett. 92, 093903 (2004).
[CrossRef] [PubMed]

J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
[CrossRef] [PubMed]

A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
[CrossRef] [PubMed]

2002

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Two-photon coincidence imaging with a classical source," Phys. Rev. Lett. 89, 113601 (2002).
[CrossRef] [PubMed]

1995

T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
[CrossRef] [PubMed]

1994

A. V. Belinski and D. N. Klyshko, "Two-photon optics: diffraction, holography, and transformation of two-dimensional signals," J. Exp. Theor. Phys. 78, 259-262 (1994).

1975

J. W. Goodman, "Statistical properties of leaser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), pp. 46-54.

J. W. Goodman, "Statistical properties of laser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), p. 53, Eq. 2.130.
[CrossRef]

Bache, M.

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
[CrossRef] [PubMed]

Basano, L.

L. Basano and P. Ottonello, "Ghost-imaging: open secrets and puzzles for undergraduates," Am. J. Phys. 75, 343-351 (2007).
[CrossRef]

Belinski, A. V.

A. V. Belinski and D. N. Klyshko, "Two-photon optics: diffraction, holography, and transformation of two-dimensional signals," J. Exp. Theor. Phys. 78, 259-262 (1994).

Bennink, R. S.

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Quantum and classical coincidence imaging," Phys. Rev. Lett. 92, 033601 (2004).
[CrossRef] [PubMed]

J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Two-photon coincidence imaging with a classical source," Phys. Rev. Lett. 89, 113601 (2002).
[CrossRef] [PubMed]

Bentley, S. J.

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Quantum and classical coincidence imaging," Phys. Rev. Lett. 92, 033601 (2004).
[CrossRef] [PubMed]

J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Two-photon coincidence imaging with a classical source," Phys. Rev. Lett. 89, 113601 (2002).
[CrossRef] [PubMed]

Berardi, V.

G. Scarcelli, V. Berardi, and Y. Shih, "Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations?" Phys. Rev. Lett. 96, 063602 (2006).
[CrossRef] [PubMed]

G. Scarcelli, V. Berardi, and Y. Shih, "Phase-conjugate mirror via two-photon thermal light imaging," Appl. Phys. Lett. 88, 061106 (2006).
[CrossRef]

Boyd, R. W.

J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Quantum and classical coincidence imaging," Phys. Rev. Lett. 92, 033601 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Two-photon coincidence imaging with a classical source," Phys. Rev. Lett. 89, 113601 (2002).
[CrossRef] [PubMed]

Brambilla, E.

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
[CrossRef] [PubMed]

Cheng, J.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

J. Cheng and S. Han, "Incoherent coincidence imaging and its applicability in x-ray diffraction," Phys. Rev. Lett. 92, 093903 (2004).
[CrossRef] [PubMed]

D'Angelo, M.

A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
[CrossRef] [PubMed]

M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
[CrossRef] [PubMed]

Ferri, F.

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

Gatti, A.

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
[CrossRef] [PubMed]

Goodman, J. W.

J. W. Goodman, "Statistical properties of leaser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), pp. 46-54.

J. W. Goodman, "Statistical properties of laser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), p. 53, Eq. 2.130.
[CrossRef]

Han, S.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

J. Cheng and S. Han, "Incoherent coincidence imaging and its applicability in x-ray diffraction," Phys. Rev. Lett. 92, 093903 (2004).
[CrossRef] [PubMed]

Howell, J. C.

J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
[CrossRef] [PubMed]

Kim, Y.-H.

M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
[CrossRef] [PubMed]

Klyshko, D. N.

A. V. Belinski and D. N. Klyshko, "Two-photon optics: diffraction, holography, and transformation of two-dimensional signals," J. Exp. Theor. Phys. 78, 259-262 (1994).

Kulik, S. P.

M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
[CrossRef] [PubMed]

Liu, H.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

Liu, Y.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

Lugiato, L. A.

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
[CrossRef] [PubMed]

Magatti, D.

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

Ottonello, P.

L. Basano and P. Ottonello, "Ghost-imaging: open secrets and puzzles for undergraduates," Am. J. Phys. 75, 343-351 (2007).
[CrossRef]

Pittman, T. B.

T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
[CrossRef] [PubMed]

Scarcelli, G.

G. Scarcelli, V. Berardi, and Y. Shih, "Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations?" Phys. Rev. Lett. 96, 063602 (2006).
[CrossRef] [PubMed]

G. Scarcelli, V. Berardi, and Y. Shih, "Phase-conjugate mirror via two-photon thermal light imaging," Appl. Phys. Lett. 88, 061106 (2006).
[CrossRef]

A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
[CrossRef] [PubMed]

Sergienko, A. V.

T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
[CrossRef] [PubMed]

Shen, X.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

Shih, Y.

G. Scarcelli, V. Berardi, and Y. Shih, "Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations?" Phys. Rev. Lett. 96, 063602 (2006).
[CrossRef] [PubMed]

G. Scarcelli, V. Berardi, and Y. Shih, "Phase-conjugate mirror via two-photon thermal light imaging," Appl. Phys. Lett. 88, 061106 (2006).
[CrossRef]

A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
[CrossRef] [PubMed]

M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
[CrossRef] [PubMed]

Shih, Y. H.

T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
[CrossRef] [PubMed]

Strekalov, D. V.

T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
[CrossRef] [PubMed]

Valencia, A.

A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
[CrossRef] [PubMed]

Wei, Q.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

Zhang, M.

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

Am. J. Phys.

L. Basano and P. Ottonello, "Ghost-imaging: open secrets and puzzles for undergraduates," Am. J. Phys. 75, 343-351 (2007).
[CrossRef]

Appl. Phys. Lett.

G. Scarcelli, V. Berardi, and Y. Shih, "Phase-conjugate mirror via two-photon thermal light imaging," Appl. Phys. Lett. 88, 061106 (2006).
[CrossRef]

J. Exp. Theor. Phys.

A. V. Belinski and D. N. Klyshko, "Two-photon optics: diffraction, holography, and transformation of two-dimensional signals," J. Exp. Theor. Phys. 78, 259-262 (1994).

Phys. Rev. A

T. B. Pittman, Y. H. Shih, D. V. Strekalov, and A. V. Sergienko, "Optical imaging by means of two-photon quantum entanglement," Phys. Rev. A 52, R3429-R3432 (1995).
[CrossRef] [PubMed]

M. Zhang, Q. Wei, X. Shen, Y. Liu, H. Liu, J. Cheng, and S. Han, "Lensless Fourier-transform ghost imaging with classical incoherent light," Phys. Rev. A 75, 021803 (2007).
[CrossRef]

Phys. Rev. Lett.

G. Scarcelli, V. Berardi, and Y. Shih, "Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations?" Phys. Rev. Lett. 96, 063602 (2006).
[CrossRef] [PubMed]

J. C. Howell, R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Realization of the Einstein-Podolsky-Rosen paradox using momentum and position entangled photons from spontaneous parametric down conversion," Phys. Rev. Lett. 92, 210403 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Two-photon coincidence imaging with a classical source," Phys. Rev. Lett. 89, 113601 (2002).
[CrossRef] [PubMed]

A. Gatti, E. Brambilla, M. Bache, and L. A. Lugiato, "Ghost imaging with thermal light: comparing entanglement and classical correlation," Phys. Rev. Lett. 93, 093602 (2004).
[CrossRef] [PubMed]

F. Ferri, D. Magatti, A. Gatti, M. Bache, E. Brambilla, and L. A. Lugiato, "High-resolution ghost image and ghost diffraction experiments with thermal light," Phys. Rev. Lett. 94, 183602 (2005).
[CrossRef] [PubMed]

A. Valencia, G. Scarcelli, M. D'Angelo, and Y. Shih, "Two-photon imaging with thermal light," Phys. Rev. Lett. 94, 063601 (2005).
[CrossRef] [PubMed]

M. D'Angelo, Y.-H. Kim, S. P. Kulik, and Y. Shih, "Identifying entanglement using quantum ghost interference and imaging," Phys. Rev. Lett. 92, 233601 (2004).
[CrossRef] [PubMed]

R. S. Bennink, S. J. Bentley, and R. W. Boyd, "Quantum and classical coincidence imaging," Phys. Rev. Lett. 92, 033601 (2004).
[CrossRef] [PubMed]

J. Cheng and S. Han, "Incoherent coincidence imaging and its applicability in x-ray diffraction," Phys. Rev. Lett. 92, 093903 (2004).
[CrossRef] [PubMed]

Other

J. W. Goodman, "Statistical properties of leaser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), pp. 46-54.

J. W. Goodman, "Statistical properties of laser speckle patterns," in Laser Speckle and Related Phenomena, J. C. Dainty, ed. (Springer-Verlag, 1975), p. 53, Eq. 2.130.
[CrossRef]

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Figures (5)

Fig. 1
Fig. 1

Schematic of the setups discussed in the text, according to offline processing. The upper part represents the main body, common to both the TLGI device and the threshold device; optical data are sent to the PC memory for processing at the end of the acquisition. GGD, ground glass disk; BS, 50% beam splitter; B1, reference beam; CCD, camera; SP, speckle pattern recorded by the camera; B2, object beam passing through the mask OM; BD, bucket detector for measuring the total intensity crossing the mask; BDO, output of the BD. (a) Attachment for the TLGI device: zero-delay correlation of SP and BDO. (b) Attachment for the threshold device: The accumulation is made for the sole patterns for which BDO > threshold ; patterns above the threshold are multiplied by the deviation of the bucket output from its mean ( BDO W ¯ ) and then summed.

Fig. 2
Fig. 2

(Color online) Images of the two-hole mask obtained when a single laser illuminates the GGD; the speckle intensities are distributed according to a negative exponential. (a) The result is obtained as the centered weighted sum of all patterns. (b) The result is obtained as the centered weighted sum of the sole images selected by the threshold level (955 patterns out of 2000).

Fig. 3
Fig. 3

(Color online) Intensity distributions of the speckle pattern produced by two pseudothermal sources. (a) Only one laser shines on one circular zone of the GGD. (b) Two lasers shine on two nonoverlapping circular zones of the GGD.

Fig. 4
Fig. 4

(Color online) Same as Fig. 2 when two lasers illuminate the GGD.

Fig. 5
Fig. 5

(Color online) Computer simulations for BMM (left) and threshold (right). Upper graphs: gamma parameter = 1 . Lower graphs: gamma parameter = 3 .

Equations (6)

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

R ( i , j ) = s = 1 s = N S [ W ( s ) F s ( i , j ) ] .
R ( i , j ) = s = 1 s = N S { [ W ( s ) W ¯ ] F s ( i , j ) } + W ¯ s = 1 s = N S [ F s ( i , j ) ] ,
R o ( i , j ) = s = 1 s = N S { [ W ( s ) W ¯ ] F s ( i , j ) } .
R o ( i , j ) = R ( i , j ) W ¯ N S F ¯ .
R o ( i , j ) = χ M C F o .
P ( I ) = ( m I ) m I m 1 exp ( m I I ) Γ ( m ) ,

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