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Coherence vortices in partially coherent beams
Optics Communications, 2003It is demonstrated that the spectral degree of coherence of a partially coherent beam may possess isolated pairs of points at which its phase is singular, and that in the neighborhood of these points the phase may possess a vortex structure. Partially coherent beams consisting of Hermite-Gaussian modes are considered as an example.
Gbur, G.J., Visser, T.D.
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Coherent diffractive imaging and partial coherence
Physical Review B, 2007We formulate coherent diffractive imaging in the framework of partially spatially coherent diffraction. We find that the reconstruction can be critically dependent on the degree of coherence in the illuminating field and that even a small departure from full coherence may invalidate the conventional assumption that a mapping exists between an exit ...
Williams, Garth J. +3 more
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GEOPHYSICS, 1993
Partially coherent migration reduces the spurious details introduced by velocity macro‐model imperfections. In a partially coherent migration, instead of summing coherently over the full aperture to achieve maximum lateral resolution, (1) a coherent stack is performed over a limited window width, and then (2) the collection of coherent stacks for ...
Delman Lee +2 more
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Partially coherent migration reduces the spurious details introduced by velocity macro‐model imperfections. In a partially coherent migration, instead of summing coherently over the full aperture to achieve maximum lateral resolution, (1) a coherent stack is performed over a limited window width, and then (2) the collection of coherent stacks for ...
Delman Lee +2 more
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Twisting partially coherent light
Optics Letters, 2018Twisted Gaussian Schell-model beams were introduced 25 years ago as a celebrated example of a "genuinely two-dimensional" partially coherent wavefield. Today, a definite answer about the effect that a twist phase should produce on an arbitrary cross-spectral density has not yet been reached. In the present Letter, the necessary and sufficient condition
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Partially coherent Ince–Gaussian beams
Optics Letters, 2020We report on the study and generation of Ince–Gaussian beams in the spatially partially coherent regime. The inherent random fluctuations both in time and space of these partially coherent fields make their characterization difficult. Our results show that the cross-correlation function (CCF) provides insight into the composition of the Ince–Gaussian ...
Adad Yepiz +2 more
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Non-diffracting partially coherent waves with binomial coherence
Journal of the Optical Society of America A, 2022Comprehensive analysis of non-diffracting optical waves with two-point binomial coherence function (BCF) is presented. This coherence function consists of two terms, each depending on either separation of points or the central point. We establish the necessary and sufficient conditions for nonnegative definiteness of the BCFs.
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Partially coherent Pearcey–Gauss beams
Optics Letters, 2020We investigate the dynamics of partially coherent Pearcey–Gauss beams propagating in free space, theoretically and experimentally. They are produced by introducing the degree of coherence (DOC) function with Gaussian Schell-model correlation into the light source in the frequency domain.
Xiaoyan Zhou, Zihao Pang, Daomu Zhao
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1978
When discussing the theory of interference and diffraction of waves, one usually assumes that the fields remain perfectly sinusoidal for all values of time. This is obviously an idealized situation and we know that the radiation from an ordinary light source consists of finite* size wave trains, a typical time variation of which is shown in Fig.
Ajoy K. Ghatak, K. Thyagarajan
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When discussing the theory of interference and diffraction of waves, one usually assumes that the fields remain perfectly sinusoidal for all values of time. This is obviously an idealized situation and we know that the radiation from an ordinary light source consists of finite* size wave trains, a typical time variation of which is shown in Fig.
Ajoy K. Ghatak, K. Thyagarajan
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Partially coherent vectorial nonparaxial beams
Journal of the Optical Society of America A, 2004Generalized vectorial Rayleigh-Sommerfeld diffraction integrals are developed for the cross-spectral-density matrices of spatially partially coherent beams. Using the Gaussian Schell-model (GSM) beam as an example, we derive the expressions for the propagation of cross-spectral-density matrices and intensity of partially coherent vectorial nonparaxial ...
Kailiang, Duan, Baida, Lü
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1986
As was made clear in the previous chapter on synchronization, an ideal coherent detector with no carrier phase error does not exist in practice. The best we can hope for is a phase error that constantly fluctuates around the mean value zero. In this chapter we will give a statistical description of the steady state phase error and study both optimum ...
John B. Anderson +2 more
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As was made clear in the previous chapter on synchronization, an ideal coherent detector with no carrier phase error does not exist in practice. The best we can hope for is a phase error that constantly fluctuates around the mean value zero. In this chapter we will give a statistical description of the steady state phase error and study both optimum ...
John B. Anderson +2 more
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