If the first and the second diffusers are both in motion, it is well known that the doubly scattered amplitude does not generally obey Gaussian statistics. Nematic, cholesteric, and smectic liquid crystals in the isotropic and ordered phases are considered. The particles, which serve as nuclei for condensation are termed as condensation nuclei or cloud condensation nuclei. The biomedical applicability of this diffuse correlation probe is illus- trated in studies of the depth of burned tissues. Detailed discussions are given of the incoherent fields which are generated by superposing the outputs of many stationary sources. It is shown that any quantum state of the field may be expanded in terms of them in a unique way. .
The influence on light scattering by unusual properties of liquid crystals such as the marked anisotropy, gyrotropy, and the presence of a regular periodic structure is examined in detail. Mechanical processes producing aerosols may be natural, like windblown dust, sea salt spray, and volcanoes, or man-made, such as industrial activities, burning of fossil fuels, and the alteration of natural surface cover. Temporal coherence of black-body radiation, spatial coherence of Lambertian and non-Lambertian sources, and the interaction of matter with radiation of any state of coherence are emphasized. First-principles modeling of electromagnetic scattering by discrete and discretely heterogeneous random media First-principles modeling of electromagnetic scattering by discrete and discretely heterogeneous. Both beginners and experienced canconfidently rely on this volume to confirm their own understandingor to help interpret their results. © 1997 Optical Society of America. We demonstrate the utility of inverse scattering algorithms for reconstructing images of the spatially varying dynamical properties of turbid media.
Theoretical curves are calculated for a specific form of the correlation function of the dielectric susceptibility. In order to keep the classical limit of quantum electrodynamics plainly in view, extensive use is made of the coherent states of the field. These fields are all shown to have intimately related properties, some of which have been known for the particular case of blackbody radiation. Andererseits erlaubt gerade die Tatsache, daß das Plasma für die Kaliumresonanzlinien optisch dick; ist und die Strahlung hier annähernd Hohlraumstrahlungsintensität bei der…. We show that it does not depend on the statistical properties of S when the number of grains tends to infinity. In either case electromagnetic scattering must be modeled in terms of appropriate optical observables, i.
In this paper, the connection between the statistics of photon counts and the properties of electron density fluctuations is discussed in detail, concentrating on the first and second moment of the photon count distribution. In either case electromagnetic scattering must be modeled in terms of appropriate optical observables, i. It has been suggested 1 that counting photons scattered from a single-mode laser beam passing through a plasma, may be used for determining correlations in the plasma. In particular, the presence of the Mandelstam-Brillouin doublet is put into evidence through the time behavior of a non-Poissonian statistical term, by using an explicit form of the two-particle correlation function. It is shown how from the equation of continuity alone, an invariant can be derived. Electromagnetic scattering orption by particles can also affect the energy budget of a discte rom medium hence various ambient physical chemical processes.
Expansions are also developed for arbitrary operators in terms of products of the coherent state vectors. The temporal fluctuations in the intensity of light scattered by a moving layer of emulsions and suspensions containing Brownian particles are investigated experimentally, and a comparison is made with light scattered by a translating phase screen. Cite this chapter as: Pusey P. It is generally believed that timeharmonic Maxwell's equations can accurately describe elastic electromagnetic scattering by macroscopic particulate media that change in time much mo slowly than the incident electromagnetic field. An expression is obtained for the intensity distribution for the case of a uniformly illuminated scattering volume and the moments are obtained for an arbitrary illumination profile. A particular form is exhibited for the density operator which makes it possible to carry out many quantum-mechanical calculations by methods resembling those of classical theory. The meaning of this invariant is that the largest scales of the fluctuations of density are determined by the initial conditions of the problem and represent permanent features of the system.
The measure of second-order coherence is then introduced in connection with the analysis of a simple interference experiment and some of the more important second-order coherence effects are studied. However, dict solutions of these equations for discte rom media had been impracticable until quite cently. These states, which reduce the field correlation functions to factorized forms, are shown to offer a convenient basis for the description of fields of all types. For stable plasmas in a steady state, the results are written in terms of the distribution functions of the electron and ion velocities. The effect of a large spatial correlation in a scattering medium on the spatial coherence of the scattered field is presented. The method is applied to the study of the correlation length in a liquid crystal cell under a dc electric field. The intensity fluctuations of the scattered light are detected through an imaging system, which collects the light emanating only from a limited volume in the medium.
The Topic facet will reveal the high-level topics associated with the articles returned in the search results. This topic browser contains over 2400 terms and is organized in a three-level hierarchy. Higher-order moments of the distribution of photon counts are related to an ensemble average of higher-order products of the electric field. The modulation effect can be characterized by the photoelectron bunching effect. Experimental results showed that an increase of the external electric field gives rise to a decrease of the correlation time, and the shape of the correlation function changes from an exponential shape to a Gaussian shape. It was found that the phenomenon can be interpreted due to the statistical effect of the simple stochastic process, i.
The particles produced by mechanical processes in general are coarse with a size of a few micrometers while fine submicrometer particles are formed by condensation. S0740-3232 97 02301-6 Statistical properties of scattered field from nematic liquid crystals in the dynamic scattering mode were studied by using the intensity correlation technique. Calculated moments are compared with those measured for dilute solutions of polystyrene spheres. The incident wave is assumed to be plane and ideally monochromatic. Nato Advanced Study Institutes Series Series B: Physics , vol 23. Topics can be refined further in the search results. The problem of taking into account multiple scattering is discussed.
Author by : Bruce J. Abstract Statistical properties of laser light doubly scattered by two diffusers ordered along the optical axis are studied. Note the Boolean sign must be in upper-case. In this paper the fluctuations of density in a compressible fluid under conditions of homogeneous isotropic turbulence are considered. All aerosol particles are formed either by mechanical processes or by condensation of gases and vapors.
The computation is carried out taking account of space and time averaging by the detector. The article concludes with a discussion of various transient superposition effects, such as light beats and interference fringes produced by independent light beams. These expansions are discussed as a general method of representing the density operator for the field. The new applications include studies of interacting particles in solution Chapter 4 ; scaling approaches to the dynamics of polymers, including polymers in semidilute solution Chapter 5 ; the use of both Fabry-Perot interferometry and photon correlation spectroscopy to study bulk polymers Chapter 6 ; studies of micelIes and microemulsions Chapter 8 ; studies of polymer gels Chapter 9. The general statistical description of the field is discussed in some detail. A review is presented of various recent investigations on the classical optical radiation laws in the light of the modern concepts of coherence and statistical optics.