Journal ArticleDOI
Some fundamental properties of speckle
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TLDR
In this paper, the distribution of scale sizes in a speckle pattern (i.e., the Wiener spectrum) is investigated from a physical point of view, and it is shown that adding M uncorrelated speckles on an intensity basis can reduce the contrast by 1/√M.Abstract:
A speckle pattern formed in polarized monochromatic light may be regarded as resulting from a classical random walk in the complex plane. The resulting irradiance fluctuations obey negative exponential statistics, with ratio of standard deviation to mean (i.e., contrast) of unity. Reduction of this contrast, or smoothing of the speckle, requires diversity in polarization, space, frequency, or time. Addition of M uncorrelated speckle patterns on an intensity basis can reduce the contrast by 1/√M. However, addition of speckle patterns on a complex amplitude basis provides no reduction of contrast. The distribution of scale sizes in a speckle pattern (i.e., the Wiener spectrum) is investigated from a physical point of view.read more
Citations
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Journal ArticleDOI
Probability of Error And Radiometric Resolution for Target Discrimination in Radar Images
TL;DR: Statistical detection theory is used to compare different definitions of radiometric resolution for radar images and the change in detectable contrast as a function of target contrast and noncoherent averaging, and additive thermal noise is presented.
Journal ArticleDOI
Generalized Discrete Radon Transforms and Their Use in the Ridgelet Transform
Flavia Colonna,Glenn R. Easley +1 more
TL;DR: A new class of Radon transforms in a discrete setting for the purpose of applying them to the ridgelet and curvelet transforms is introduced and the effectiveness of some types of the generalized Radon transform in reducing a type of noise known as speckle that is present in synthetic aperture radar (SAR) imagery is studied.
Journal ArticleDOI
Boundary Enhancement and Speckle Reduction for Ultrasound Images via Salient Structure Extraction
TL;DR: Applications of US image segmentation show that although the proposed algorithm cannot remove the speckle noise completely and may discard weak anatomical structures in some case, it still provides a considerable gain to US image processing for computer-aided diagnosis.
Journal ArticleDOI
Review on short-wavelength infrared laser gated-viewing at Fraunhofer IOSB
Benjamin Göhler,Peter Lutzmann +1 more
TL;DR: In this article, the authors present a review of the work that has been done at Fraunhofer IOSB (and its predecessor institutes) in the past ten years in the area of laser gated-viewing in the short-wavelength infrared (SWIR) band.
References
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ReportDOI
Statistical properties of laser sparkle patterns
TL;DR: In this article, the first order statistics of the observed electric-field strength, the observed light intensity, and observed light phase are examined, and the autocorrelation functions of the complex field and intensity processes are investigated, and that of the electric field is found to be proportional to the Fourier transform of the light intensity distribution incident on the scattering surface.
Book ChapterDOI
Statistical Properties of Laser Speckle Patterns
TL;DR: In this article, the first-order statistics of the complex amplitude, intensity and phase of speckle are derived for a free-space propagation geometry and for an imaging geometry.
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Some Aspects of Diffraction Theory and their Application to the Ionosphere
TL;DR: In this paper, the Fourier approach is extended to deal with problems of ''random'' diffraction, for which purpose the use of auto-correlation functions is introduced and explained in physical terms.
Investigation of molecular motions in supercooled liquids by Mossbauer scattering D C Champeney and F W D Woodhams Some Aspects of Diffraction Theory and their Application to the Ionosphere
J A Ratcliffe,D C Champeney +1 more
TL;DR: In this article, the Fourier approach is extended to deal with problems of ''random'' diffraction, for which purpose the use of auto-correlation functions is introduced and explained in physical terms.
Journal ArticleDOI
XII. On the resultant of a large number of vibrations of the same pitch and of arbitrary phase
TL;DR: In this article, the resultant of a large number of vibrations of the same pitch and of arbitrary phase is discussed. But the authors focus on the effect of the phase of the vibrations.