Stochastic interference of partially coherent light multiple scattered by a random medium is considered. The relationship between the second- and third-order moments of intensity fluctuations in random interference patterns, the coherence function of probe radiation, and the probability density of path differences for the interfering partial waves in the medium are established. The obtained relationships were verified using the statistical analysis of spectrally selected fluorescence radiation emitted by the laser-pumped dye-doped random medium. Rhodamine 6G water solution was applied as the doping agent for the ensembles of densely packed silica grains which were pumped by the CW radiation (532 nm) from the diode-pumped solid state laser. Experimentally observed abrupt decay of the second- and third-order moments of fluorescence intensity fluctuations for the wavelengths ranging from 620 nm to 680 nm is interpreted in terms of amplification of spontaneous emission at large dye concentrations. This paper discusses the new optical probe of random media defined as "the reference-free path length interferometry with the intensity moments analysis".

Представлены данные анализа гиперспектральных изображений онкопатологий кожи человека. Изображения содержали данные спектров обратного рассеяния нормальной кожи и патологий. На основании данных о содержании основных хромофоров кожи предложен метод диагностики злокачественных пигментных образований кожи. Ключевые слова: гиперспектральная визуализация, спектроскопия обратного рассеяния, меланома, невус.

Polylactide foaming as the key stage in laboratory preparation of highly porous biocompatible matrices used as scaffold prototypes was monitored based the effect of dynamic light scattering in expanding polylactide foams. Intensity fluctuations of scattered laser radiation in the course of foam expansion were analyzed using ensemble-averaged estimates of the speckle lifetime within a running window in the time domain. It was found that, in contrast to the commonly used correlation time of intensity fluctuations, the values of the average speckle lifetime are invariant with respect to the type of dynamics of phase fluctuations of partial components in scattered radiation. This makes it possible to relate this parameter to microscopic mobility of interphase boundaries in the foam in the absence of a priori information on the law of motion relating these boundaries at the microscopic level. The proposed approach in combination with the developed phenomenological model describing the relationship between the average speckle lifetime and the current values of the foam volume, as well as its first-time derivative made it possible to interpret the features of foam structure formation.

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A method for visualization and identification of nucleotide sequences is proposed based on the synthesis of phase screens displaying the structure of the analyzed sequences and reconstruction of binary maps of the extreme values of the local Stokes vector components in the diffraction zone. This diffraction zone is formed due to reading out the phase screen by a coherent collimated beam with two orthogonally polarized (x-y) components. With different phase delays of the x-y components of the readout beam introduced by the phase screen elements, this causes a variety of local polarization states in the diffraction zone. The discrimination level for the local component of the Stokes vector chosen for the binary mapping is established near the extreme value for this component. Computer verification of the proposed method using nucleotide sequences for various strains of the model African swine fewer (ASF) virus as the test objects shows its high efficiency in the detection of differences between two compared sequences corresponding to the same type of infectious agent. Analysis of the model data for the strains under study made it possible to establish a power-law character of correlation coefficients of the synthesized binary distributions of extreme local polarization states depending on the discrimination threshold detuning from the maximum value of the Stokes vector component used for the mapping.