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The Statistical and Correlation Properties of Light Scattered by a Random Phase Screen

  • G. Parry
  • P. N. Pusey
  • E. Jakeman
  • J. G. McWhirter
Conference paper

Abstract

We report measurements of the statistical and correlation properties of laser light scattered by a random phase screen produced in the laboratory by turbulent mixing of the convective hot air flow above an electric heater and the surrounding cooler air. A phase screen is a localized region of space containing refractive index variations which cause random fluctuations in the phase of electromagnetic radiation propagating through it. On further free propagation of the emergent radiation, intensity fluctuations develop through two distinct mechanisms. Firstly, the individual refractive index inhomogeneities act as lenses which bend the light “rays” and produce a random focussing of the radiation. Secondly, further from the screen, the radiation scattered by different, independent inhomogeneities can overlap to form fringes and more complex interference patterns (e.g. speckle). Phase screens have been of interest for many years because of their role in various natural phenomena such as the fading of radio signals reflected from the ionosphere [1], the scintillation of distant radio sources due to the solar wind [2] and the twinkling of starlight caused by atmospheric fluctuations [3]. Nevertheless our measurements appear to be the first which cover a wide range of screen-detector distance, thereby providing focussing curves such as Figure 2.

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References

  1. 1.
    H.G. Booker, J.A. Ratcliffe and D.H. Shinn, Phil. Trans. Roy. Soc. 242, 579 (1950).ADSCrossRefzbMATHMathSciNetGoogle Scholar
  2. 2.
    L.T. Little and A. Hewish, Mon. Not. R. Ast. Soc. 134, 221, (1966) and 138, 393, (1968).Google Scholar
  3. 3.
    E. Jakeman, E.R. Pike and P.N. Pusey, Nature 263, 215 (1976).ADSCrossRefGoogle Scholar
  4. 4.
    G. Parry, P.N. Pusey, E. Jakeman and J.G. McWhirter, Opt. Commun. 22, 195 (1977).ADSCrossRefGoogle Scholar
  5. 5.
    E. Jakeman and J.G. McWhirter, J. Phys. A(GB) 10, 1599 (1977).ADSCrossRefGoogle Scholar
  6. 6.
    Y. Furuhama, Radio Science 10, 1037, (1975).ADSCrossRefGoogle Scholar
  7. 7.
    P.N. Pusey, in Photon Correlation Spectroscopy and Velocimetrzo, eds. H.Z. Cummins and E.R. Pike, ( Plenum, New York, 1977 ).Google Scholar
  8. 8.
    E. Jakeman and P.N. Pusey, IEEE Trans. Antennas Propagat. AP-24, 806, (1976).Google Scholar
  9. 9.
    E. Jakeman, J. Phys. A(GB)8, L23, (1975).Google Scholar
  10. 10.
    P.N. Pusey, J. Phys. D(GB)9, 1399, (1976).Google Scholar

Copyright information

© Springer Science+Business Media New York 1978

Authors and Affiliations

  • G. Parry
    • 1
  • P. N. Pusey
    • 1
  • E. Jakeman
    • 1
  • J. G. McWhirter
    • 1
  1. 1.Royal Signals and Radar Establishment, MalvernUK

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