The first-order phase transition of an MBBA nematic liquid crystal with benzene impurity has been studied by the critical opalescence method at a large cell thickness. Opalescence observed two points. spatial transverse parameters domains are determined from Fraunhofer diffraction. hypothesis about longitudinal correlation parameter is equal to length proposed.

Analytical solutions are presented for Fraunhofer diffraction by the following nonspherical particles: rectangular parallelepiped, hexagonal cylinder, spheroid, and threeaxis ellipsoid. Using these solutions, numerical results for the diffracted intensity of these particles in specific orientations and 3-D random orientation for an ensemble of particles of the same size are presented and discus...

The parallelism between diffraction and interference in optics and quantum interference in Josephson junctions is discussed and studied in details. The interdisciplinary character of the present work is highlighted through specific examples. The Fraunhofer-like pattern of the maximum Josephson current in a single Josephson junction and the periodic field dependence of the critical current in tw...

We introduce a noniterative image-reconstruction technique for coherent diffractive imaging. Through the application of differential and integral operators, an extended reference can be used to recover the complex-valued transmissivity of an object, in closed form, from a measurement of its far-field (Fraunhofer) diffraction intensity. We demonstrate the feasibility of this approach, using a re...

An optical waveguide structure, which increases the far field radiation angle two times than that of conventional fiber, is designed and analyzed for the research of optical phased array. The structure improves the scanning scope of the optical fiber phased array effectively through designing the shape and the refractive index profile of the single mode fiber. Far field characteristic of this s...

We present what we believe to be the first experimental demonstration of a novel coherent lensless imaging technique: holography with extended reference by autocorrelation linear differential operator. Upon taking derivatives of the field autocorrelation this technique allows the direct reconstruction of an object complex-valued transmissivity from a measurement of its Fraunhofer diffraction pa...

We provide a detailed analysis of the three-dimensional spatial coherence properties of light speckles, based on very general assumptions. We show that, while in the deep Fresnel region close to the source the longitudinal coherence of speckles is ruled by the laws of ordinary diffraction, on approach to the Fraunhofer zone the longitudinal coherence length tends to become infinite. We offer bo...

Differential Fourier holography (DFH) gives an exact mathematical solution of the inverse problem of diffraction in the Fraunhofer regime. After the first publication [Opt. Express15, 9954 (2007)], DFH was successfully applied in many experiments to obtain amplitude and phase information about two-dimensional images. In this paper, we demonstrate numerically the possibility to apply DFH also fo...