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Abstract: It is known that the degree of polarization of a light beam is, in general, different at different points in space. In this paper we show that there is a class of quasi-homogeneous sources which generate beams whose degree of polarization does not change as the beam propagates. [Copyright &y& Elsevier]

Abstract: Detection depth and sampling volume of polarized light in highly turbid, cylindrically-shaped samples are estimated using pathlength distributions calculated from a polarization-sensitive Monte Carlo model. Due to defined ranges of the polarized light pathlength distribution, the estimated penetration depth and the interrogated volume of the polarization-maintaining photon subpopulation are smaller than those of the whole collected photon population, the latter exhibiting a wider pathlength distribution resulting from multiple scattering. It is also demonstrated that the spatial interrogation extent of polarized light in turbid media is greatly affected by the experimental detection geometry. [Copyright &y& Elsevier]

Abstract: The use of polarization information for discrimination in imaging, especially of shiny surfaces or cracks in such surfaces, is well established. This paper seeks to explore the potential of just two of the four polarization parameters per pixel (horizontal and vertical components) for discrimination in a monochromatic image using a new method: conversion of the two monochrome images into a single pseudocolored image followed by the use of Artificial Color to segment the scene in terms of color. [Copyright &y& Elsevier]

Abstract: We examined pupil-plane polarization structures for high numerical-aperture objective lenses that generate light distributions at the focal volume similar to those produced by purely radial and azimuthal polarizations. The engineered structures can be dynamically generated with spatial light modulators without the need for additional moving parts in the optical system. Computer simulations show that the method can be considered a valuable addition to the tools available for controlling the interaction of light with matter at the focal region. [Copyright &y& Elsevier]

Abstract: By introducing the notion of wavelength- and angle-averaged transmittance, we assess in a systematic way the possibility of achieving approximate omnidirectional antireflection in a wide spectral range by using double-layer systems. We also determine the optimum range of thicknesses for which this broadband omnidirectional antireflection occurs. [Copyright &y& Elsevier]

Abstract: We present experimental and numerical evidence of polarization selection in an isotropic CO2 laser achieved by means of an unpolarized optical feedback. This mechanism can be applied in situations where the direction of polarization plays a crucial role, including polarization coding. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a novel photonic crystal fibre (PCF) with high phase birefringence and very low group birefringence. It is composed of a solid silica core and a cladding with helix-pattern air holes. Using a full-vector finite-element method, we study the phase and group modal birefringence of such PCF at various air-hole sizes, pitches and wavelengths. Owing to this innovative structure of air holes, a high phase to group modal birefringence rate is obtained. Its phase modal birefringence is as large as 10−4 magnitude; however, the group modal birefringence of this PCF is at 10−7–10−6. The phase birefringence is 2 orders of magnitude larger than group birefringence over a broad wavelength span, which means that the light with different polarization and effective index has almost a same group velocity. As a result, the group modal birefringence that closely relates to the polarization modal dispersion is negligible. [Copyright &y& Elsevier]

Abstract: In this paper, a novel configuration of LCD projectors for efficiently polarized stereoscopic projection with improved light efficiency is presented. In the proposed scheme, polarization orientations of the analyzers in the LCD engine of one projector are rotated by 90° with respect to those of the other one, so it causes to rotate orientations of polarized outputs by 90° as well as to change operational modes of LCD panels from the normally black mode to the normally white mode or vice versa. Then, by exchanging the green color components between the modified and original LCD projectors, two orthogonally polarized views for stereoscopic projection could be obtained without use of external polarizers. Analysis on the operational mode conversions of the LCD engines with rotation of the analyzers is discussed and its experimental results are provided. [Copyright &y& Elsevier]

Abstract: New expressions are derived that predict the change of spectral density, the spectral degree of coherence and spectral degree of polarization in Young’s interference pattern when the pinholes are illuminated by an electromagnetic Gaussian Schell-mode beam. The spectral degree of polarization in the observation plane is found, in general, to take on values different from its values at each pinhole, and it changes with position at the same spatial frequency, as does the spectral density. When the light at the pinholes is completely coherent, there are singular points in the pattern, at which the spectral degree of polarization reaches minimum value. [Copyright &y& Elsevier]

Abstract: This paper focuses on the theory and practice of surface-relief holographic diffusers that can diffract scattered light forward or backward. Experimental results show that scattered light diffracted by a holographic diffuser usually possesses similar polarization to that of the incident light and that the phase range of light modulated by a diffuser must be not less than 360° for the diffuser not to produce specular transmission light. Supports for these phenomena are elaborated based on the diffraction theories of gratings. [Copyright &y& Elsevier]

Abstract: We present a method to characterize the polarization state of a light field in the continuous-variable regime. Instead of using the abstract formalism of SU(2) quasidistributions, we model polarization as the superposition of two harmonic oscillators of the same angular frequency along two orthogonal axes, much in the classical way of dealing with this variable. By describing each oscillator by an s-parametrized quasidistribution, we derive in a consistent way the final function for the polarization. We compare with previous approaches and show how this formalism works in some relevant examples. [Copyright &y& Elsevier]

Abstract: Polarization aspects of the three-dimensional optical beam reflection and refraction at dielectric interfaces are analyzed within the framework of the aberrationless approach. The power and the transversal beam profile of the cross-polarized beam are determined in the paraxial approximation. The cross-polarization phenomenon is experimentally demonstrated. Based on the theoretical and experimental results, a simple new method using an appropriate dielectric mirror is proposed for the generation of radially polarized light beams. [Copyright &y& Elsevier]

Abstract: We show that the degree of polarization for two- and three-dimensional fields can be formulated as a distance between the field correlation matrix and the identity matrix which represents completely unpolarized light. This definition is compared with previous approaches. [Copyright &y& Elsevier]

Abstract: In this paper, we analyze the polarization properties of uniform fiber Bragg gratings that are written into highly birefringent fibers. We study the evolution of the normalized Stokes parameters with wavelength for the reflected and transmitted signals. Theoretical expressions for the evolution of the Stokes parameters versus wavelength are first derived. An experimental set-up for the measurement of the polarization properties of fiber Bragg gratings for both the reflected and transmitted signals is then presented. Experimental results are finally compared with theory and a good agreement is observed. [Copyright &y& Elsevier]

Abstract: We introduce a scalar Wigner function for classical vectorial light fields embodying full information about polarization. We introduce global and local Stokes parameters with simple and natural transformation laws under ABCD transformations and polarization changing devices. We apply this formalism to the free propagation of vectorial Gaussian–Schell waves. [Copyright &y& Elsevier]

This work describes the observed effects in the polarization resonance of the 5S1/2–5D5/2 atomic transitions of 87Rb atoms induced by both Faraday effects and coherent light induced anisotropy of the atoms when immersed in different levels of constant magnetic field intensities. Specifically, linear collision broadening and frequency shift of the polarization resonance, as a function of Rb atomic gas density, were measured in a temperature controlled magnetically shielded cell. From the results, density-dependent line broadening and line frequency shift were observed with the coefficients of (3.53 ± 0.09) × 10−10 and (−1.66 ± 0.09) × 10−10 cm3 Hz, respectively. Additionally, fluorescence and polarization signals illustrated an amplitude dependency on atomic density. [Copyright &y& Elsevier]