Abstract

A simple technique involving the use of a rotating and a stationary diffuser has been developed to vary the spatial coherence of light from a He–Ne laser. Using this technique an experimental investigation of the dependence of rotation sensitivity of Lau fringes on the spatial coherence of the illuminating wavefield has been carried out. It is observed that (i) the rotation sensitivity of Lau fringes varies in a well-defined manner as a function of the spatial coherence of the light used; (ii) the extremely good rotation sensitivity of Lau fringes can be used to great advantage (compared to the conventional double slit method) in the measurement of the spatial coherence of a wavefield; (iii) Lau fringes are formed at various levels of spatial coherence and as such it appears that the Lau effect need not be associated with an incoherent optical field.

© 1989 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. E. Lau, “Beugungserscheinungen an Doppelrastern,” Ann. Phys. 6, 417 (1948).
    [CrossRef]
  2. R. J. Sudol, B. J. Thompson, “Lau Effect: Theory and Experiment,” Appl. Opt. 20, 1107 (1981); F. Gori, “Lau Effect and Coherence Theory,” Opt. Commun. 31, 4 (1979).
    [CrossRef] [PubMed]
  3. J. Jahns, A. W. Lohmann, “The Lau Effect (A Diffraction Experiment with Incoherent Illumination),” Opt. Commun. 28, 263 (1979).
    [CrossRef]
  4. G. J. Swanson, E. N. Leith, “Analysis of the Lau Effect and Grating Imaging,” J. Opt. Soc. Am. A 2, 789 (1985).
    [CrossRef]
  5. J. Jahns, A. W. Lohmann, J. Ojeda-Castaneda, “Talbot and Lau Effects, a Parageometrical Approach,” Opt. Acta 31, 313 (1984).
    [CrossRef]
  6. K. Patorski, “Incoherent Superposition of Multiple Self Imaging Lau Effect and Moire Fringe Explanation,” Opt. Acta 30, 745 (1983).
    [CrossRef]
  7. S. Chitralekha, K. V. Avudainayagam, S. V. Pappu, P. S. Ramanujam, “Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect,” J. Mod. Opt., in press.
  8. J. Ojeda-Castaneda, E. E. Sicre, “Theta Modulation Decoder Based on the Lau Effect,” Opt. Commun. 59, 87 (1986).
    [CrossRef]
  9. S. Lowenthal, D. Joyeux, “Speckle Removal by a Slowly Moving Diffuser Associated with a Motionless Diffuser,” J. Opt. Soc. Am. 61, 847 (1971).
    [CrossRef]
  10. B. J. Thompson, E. Wolf, “Two Beam Interference with Partially Coherent Light,” J. Opt. Soc. Am. 47, 895 (1957).
    [CrossRef]

1986

J. Ojeda-Castaneda, E. E. Sicre, “Theta Modulation Decoder Based on the Lau Effect,” Opt. Commun. 59, 87 (1986).
[CrossRef]

1985

1984

J. Jahns, A. W. Lohmann, J. Ojeda-Castaneda, “Talbot and Lau Effects, a Parageometrical Approach,” Opt. Acta 31, 313 (1984).
[CrossRef]

1983

K. Patorski, “Incoherent Superposition of Multiple Self Imaging Lau Effect and Moire Fringe Explanation,” Opt. Acta 30, 745 (1983).
[CrossRef]

1981

1979

J. Jahns, A. W. Lohmann, “The Lau Effect (A Diffraction Experiment with Incoherent Illumination),” Opt. Commun. 28, 263 (1979).
[CrossRef]

1971

1957

1948

E. Lau, “Beugungserscheinungen an Doppelrastern,” Ann. Phys. 6, 417 (1948).
[CrossRef]

Avudainayagam, K. V.

S. Chitralekha, K. V. Avudainayagam, S. V. Pappu, P. S. Ramanujam, “Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect,” J. Mod. Opt., in press.

Chitralekha, S.

S. Chitralekha, K. V. Avudainayagam, S. V. Pappu, P. S. Ramanujam, “Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect,” J. Mod. Opt., in press.

Jahns, J.

J. Jahns, A. W. Lohmann, J. Ojeda-Castaneda, “Talbot and Lau Effects, a Parageometrical Approach,” Opt. Acta 31, 313 (1984).
[CrossRef]

J. Jahns, A. W. Lohmann, “The Lau Effect (A Diffraction Experiment with Incoherent Illumination),” Opt. Commun. 28, 263 (1979).
[CrossRef]

Joyeux, D.

Lau, E.

E. Lau, “Beugungserscheinungen an Doppelrastern,” Ann. Phys. 6, 417 (1948).
[CrossRef]

Leith, E. N.

Lohmann, A. W.

J. Jahns, A. W. Lohmann, J. Ojeda-Castaneda, “Talbot and Lau Effects, a Parageometrical Approach,” Opt. Acta 31, 313 (1984).
[CrossRef]

J. Jahns, A. W. Lohmann, “The Lau Effect (A Diffraction Experiment with Incoherent Illumination),” Opt. Commun. 28, 263 (1979).
[CrossRef]

Lowenthal, S.

Ojeda-Castaneda, J.

J. Ojeda-Castaneda, E. E. Sicre, “Theta Modulation Decoder Based on the Lau Effect,” Opt. Commun. 59, 87 (1986).
[CrossRef]

J. Jahns, A. W. Lohmann, J. Ojeda-Castaneda, “Talbot and Lau Effects, a Parageometrical Approach,” Opt. Acta 31, 313 (1984).
[CrossRef]

Pappu, S. V.

S. Chitralekha, K. V. Avudainayagam, S. V. Pappu, P. S. Ramanujam, “Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect,” J. Mod. Opt., in press.

Patorski, K.

K. Patorski, “Incoherent Superposition of Multiple Self Imaging Lau Effect and Moire Fringe Explanation,” Opt. Acta 30, 745 (1983).
[CrossRef]

Ramanujam, P. S.

S. Chitralekha, K. V. Avudainayagam, S. V. Pappu, P. S. Ramanujam, “Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect,” J. Mod. Opt., in press.

Sicre, E. E.

J. Ojeda-Castaneda, E. E. Sicre, “Theta Modulation Decoder Based on the Lau Effect,” Opt. Commun. 59, 87 (1986).
[CrossRef]

Sudol, R. J.

Swanson, G. J.

Thompson, B. J.

Wolf, E.

Ann. Phys.

E. Lau, “Beugungserscheinungen an Doppelrastern,” Ann. Phys. 6, 417 (1948).
[CrossRef]

Appl. Opt.

J. Opt. Soc. Am.

J. Opt. Soc. Am. A

Opt. Acta

J. Jahns, A. W. Lohmann, J. Ojeda-Castaneda, “Talbot and Lau Effects, a Parageometrical Approach,” Opt. Acta 31, 313 (1984).
[CrossRef]

K. Patorski, “Incoherent Superposition of Multiple Self Imaging Lau Effect and Moire Fringe Explanation,” Opt. Acta 30, 745 (1983).
[CrossRef]

Opt. Commun.

J. Jahns, A. W. Lohmann, “The Lau Effect (A Diffraction Experiment with Incoherent Illumination),” Opt. Commun. 28, 263 (1979).
[CrossRef]

J. Ojeda-Castaneda, E. E. Sicre, “Theta Modulation Decoder Based on the Lau Effect,” Opt. Commun. 59, 87 (1986).
[CrossRef]

Other

S. Chitralekha, K. V. Avudainayagam, S. V. Pappu, P. S. Ramanujam, “Experimental Verification of the Lateral Periodicity of Axially Periodic Incoherent Fields Using the Lau Effect,” J. Mod. Opt., in press.

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 (4)

Fig. 1
Fig. 1

Schematic diagrams of the setups used in carrying out the Lau experiment and Young’s double slit experiment: (a) setup of the conventional Lau experiment; (b) setup of the Lau experiment used in this study; (c) setup of Young’s double slit experiment used in this study; EWLS, extended white light source; G1, G2, gratings; L, lens; S observation plane; f, focal length of lens L; HNLA, He–Ne laser; RD, rotating diffuser; SD, stationary diffuser; D, distance between the diffusers; Z, distance between the gratings; P, plane in which the double slit is placed (this plane corresponds to the plane of grating G1).

Fig. 2
Fig. 2

Variation of the degree of spatial coherence with the distance of separation between the diffusers. (a) Photographs of the Young fringes. (b) Corresponding intensity plots obtained from microdensitometer. Fig. 2(A): D = 0.5 mm, d = 100, μm, |γ12(0)| = 0.724. Fig. 2(B):D = 4 mm, d = 100 μm, |γ12(0)| = 0.117. Fig. 2(C): D = 7 mm, d = 100 μm, |γ12(0)| = 0.036. Fig. 2(D): D = 15 mm, d = 100 μm, D = |γ12(0)| = 0.005.

Fig. 3
Fig. 3

(a) Variation of the rotation angle θ with the distance of separation D between diffusers. (b) Variation of the transverse coherence length L with the distance of separation D between diffusers.

Fig. 4
Fig. 4

Variation of the rotation angle θ with the transverse coherence length L.

Tables (4)

Tables Icon

Table I List of Components and Measuring Instruments Used In This Study

Tables Icon

Table II Data on the Variation of the Degree of Spatial Coherence |γ12(0)| with Distance of Separation D Between Diffusers

Tables Icon

Table III Data on the Variation of Transverse Coherence Length L with the Distance of Separation D Between Diffusers

Tables Icon

Table IV Data on the Variation of Rotation Angle θ with the Distance of Separation D Between Diffusers

Equations (1)

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

V = I max - I min I max + I min = γ 12 ( 0 )

Metrics