Experimental demonstration of singular-optical colouring of regularly scattered white light

Abstract

Experimental interference modelling of the effects of colouring of a beam traversing a light-scattering medium is presented. It is shown that the result of colouring of the beam at the output of the medium depends on the magnitudes of the phase delays of the singly forward scattered partial signals. The colouring mechanism has for the first time experimentally been illustrated for a forward propagating beam through a light-scattering medium. This is showed in video-fragments of the interferograms recorded within the zero interference fringe with a gradual change of the path difference of the interfering polychromatic wave trains. Spectral investigation of the effects of colouring has been carried out using a solution of liquid crystal in a polymer matrix. The amplitude ratio of the non-scattered and the singly forward scattered interfering components significantly affects the colour intensity. It has further been established that the spectral content of the illuminating beam strongly influences the colour of the resulting radiation.

New polarization-interference approach for determination of polarization properties of birefringent media

“…Traditional polarization-sensitive methods of diagnostics 1-5,10-11, allow, in to reproduce both amplitude characteristics (refractive index, reflectivity), polarization [10][11] and phase [3][4][5]12 characteristics of the object fields and studied objects, such as birefringence, phase retardation, optical axis orientation and dichroism [1][2] . To diagnose the internal structure of optically heterogeneous objects, polarization-interference methods are usually used, such as low-coherence interferometry and optical coherence tomography (OCT) 6 .…”

Model of optical axis orientation estimation in birefringent biological tissues

“…Polarimetric [2][3] and interferometric [4][5][6] methods are often used to diagnose the properties of biological media. The interaction of polarized light with a biological medium [6][7][8] lead to change of polarization and phase of radiation.…”

Method of determining the geometric phase for linearly birefringent medium

“…Due to the polarized light propagation in optically inhomogeneous (anisotropic) medium, in addition to the conventional (dynamic) phase caused by an optical path length, an additional (geometric) phase also arises, which is determined by a change of polarization [1][2][3][4][5][6] . This phase shift depends both on the parameters of the medium [7][8][9] and on the initial polarization state. There are two groups of methods for determining the geometric phase 2 : polarimetric and interferometric.…”

“…In the first case, polarization transformations in the system [7][8][9][10][11][12] are represented as points on the Poincaré sphere, forming a contour of polarization changes (opened or closed), and the geometric phase is determined by the relative position of these points, in particular, by the surface area bounded by the contour 2,5 . In another group of methods, the geometric (as well as the dynamic) phase leads to a shift of interference peaks, and numerically can be obtained by the magnitude of this shift 4-6. The dynamic and geometric phase constitute the total phase of the beam, which manifests itself in interference [7][8][9]12 . In some interference methods, two orthogonal states of linear input polarization are used to determine the geometric phase 4 .…”

“…In this case, two interference patterns are obtained in which the shift of the interference peaks in one case is given by the sum, and in the other case by the difference of the dynamic and geometric phases. We propose another polarizationinterference method [7][8][9]12 for determining both the dynamic and geometric phases for only one input (linear) polarization state of the incident beam. In this case, the orthogonal state of polarization occurs due to the radiation propagation in the anisotropic medium.…”