Polarization imaging by use of digital holography

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A problem of the polar code construction for multiple access channels (MACs) is that they do not always achieve the whole capacity region. Although polar codes achieve the sum-capacity of symmetric MACs, polarization may induce a loss in the capacity region which prevents polar codes from achieving the whole capacity region. This paper provides a single letter necessary and sufficient condition which characterizes all the MACs that do not lose any part of their capacity region by polarization.

We present a longitudinal-differential (LD) phase distribution near the focus of a high numerical aperture (NA=0.9) aplanatic lens illuminated with a linearly polarized monochromatic plane wave. The Richards and Wolf method is used to compute field distributions. The LD phase map is obtained by analyzing the deviation of the phase of the simulated wave to the phase of a referential plane wave. We discuss the irregular wavefront spacing that is linked to the Guoy phase and disclose subtle details of the phas

Spectral induced polarization is receiving increasing attention as a tool to map subsurface properties in a non-invasive manner. Although empirical correlations have been devised to link measurements to porous medium properties, such as the time constant of the Cole-Cole model to grain size distribution and hydraulic conductivity, a comprehensive process-based model is still missing. Two fundamentally different mechanisms have been proposed so far, (i) electrical double layer polarization, in particular of

We demonstrate a concurrent polarization-retrieval algorithm based on a multi-heterodyne scanning near-field optical microscopy (MHSNOM) measurement system. This method relies on calibration of the polarization properties of the MH-SNOM using an isotropic region of the sample in the vicinity of the nanostructures of interest. We experimentally show the effectiveness of the method on a silicon form-birefringent grating (FBG) with significant polarization diversity. Three spatial dimensional near-field measur

The polarization-related properties of stimulated Brillouin scattering (SBS) processes in long, randomly birefringent, standard optical fibers are examined. Evolution equations for the pump and signal waves, in the presence of both birefringence and SBS, are provided in Jones and Stokes spaces. It is shown that in the undepleted pump regime, the amplification of the SBS signal wave is equivalent to that of a linear medium with polarization-dependent gain. The process is associated with a pair of orthogonal

Half-vortices have been recently shown to be the elementary topological defects supported by a spinor cavity exciton-polariton condensates with spin-anisotropic interactions [Y. G. Rubo, Phys. Rev. Lett. 99, 106401 (2007)]. A half-vortex is composed by an integer vortex for one circular component of the condensate, whereas the other component remains static. We analyze theoretically the effect of the splitting between TE and TM polarized eigen modes on the structure of the vortices in this system. For TE an

Introduction. Development of the fetal brain surface with concomitant gyrification is one of the major maturational processes of the human brain. First delineated by postmortem studies or by ultrasound, MRI has recently become a powerful tool for studying in vivo the structural correlates of brain maturation. However, the quantitative measurement of fetal brain development is a major challenge because of the movement of the fetus inside the amniotic cavity, the poor spatial resolution, the partial volume ef

The distributed representation of correlated images is an important challenge in applications such as multi-view imaging in camera networks or low complexity video coding. This paper addresses the problem of distributed coding of images whose correlation is driven by the motion of objects or the positioning of the vision sensors. It concentrates on the problem where images are encoded with compressed linear measurements, which are used for estimation of the correlation between images at decoder. We propose

In this paper we report the fabrication and detailed electrical characterization of a Metal-Ferroelectric-Oxide-Semiconductor Capacitor aiming at the extraction of the polarization characteristic. In order to evaluate the electrical performances of the ferroelectric over SiO2 capacitor, we propose a simple device test structure featuring an intermediate contact between the two insulators. The investigated test structures are fabricated on highly doped silicon with a gate stack including 40nm silicon dioxide

The study of the internal structures of specimens has a great importance in life and materials sciences. The principle of optical diffraction tomography (ODT) consists in recording the complex wave diffracted by an object, while changing the k vector of the illuminating wave. This way, the frequency domain of the specimen is scanned, allowing reconstructing the scattering potential of the sample in the spatial domain. This work presents a method for sub-micron tomographic imaging using multiple wavelengths

In this paper, we present a transmission polarization digital holographic microscope (Pol-DHM) that allows for imaging the state of polarization of a wave front with the acquisition of a single hologram. This apparatus records, using a CCD camera, the interference in off-axis geometry between two orthogonally polarized reference waves and an object wave transmitted through a microscopic sample and magnified by a microscope objective. Since the reference waves have orthogonal polarizations, they do not inter

In this paper we present a method for tomographic imaging using multiple wavelengths in digital holographic microscopy. This method is based on the recording at different wavelengths equally separated in the k-domain, in off- axis geometry of the interference between a reference wave and an object wave reflected by a microscopic sample and magnified by a microscope objective. A couple charged device (CCD) camera records consecutively the resulting holograms, which are then numerically reconstructed to obtai

We present a new digital two-step reconstruction method for off-axis holograms recorded on a CCD camera. First, we retrieve the complex object wave in the acquisition plane from the hologram's samples. In a second step, if required, we propagate the wave front by using a digital Fresnel transform to achieve proper focus. This algorithm is sufficiently general to be applied to sophisticated optical setups that include a microscope objective. We characterize and evaluate the algorithm by using simulated data

It is possible to determine the types and values of stator and rotor errors in magnetic circuits in a synchronous machine by measuring the induced voltage (ui) for the terminals of measurement loops (2) which can capture an image of the induction in the measurement gap, then by treating said signals.

In the search for a good dimensionally stable anode-type electrode, p-silicon (1-3 mW cm) has been chosen as the substrate material due to its high anodic stability and its reasonable cost compared to titanium and tantalum. Several p-Si/IrO2 electrodes have been prepd. by thermal decompn. at different temp. The effect of prepn. temp. on the morphol. and electrochem. properties has been investigated by SEM anal., X-ray diffraction, and cyclic voltammetry in 1 M HClO4 showing that p-Si/IrO2 prepd. at 450 DegC

The main topic of this thesis is elastic image registration for biomedical applications. We start with an overview and classification of existing registration techniques. We revisit the landmark interpolation which appears in the landmark-based registration techniques and add some generalizations. We develop a general elastic image registration algorithm. It uses a grid of uniform B-splines to describe the deformation. It also uses B-splines for image interpolation. Multiresolution in both image and deforma

Most energy saving applications of advanced fenestration systems (solar blinds, novel types of glazing and daylight redirecting devices) require a precise knowledge of their directional light transmission features. These photometric properties can be described by a Bi-directional Transmission Distribution Function (BTDF) whose experimental assessment requires appropriate equipment. A novel bi-directional transmission photogoniometer, based on digital imaging techniques, was designed and set up for that purp

We study the plasmon resonances for small two-dimensional silver particles (nanowires) with elliptical or triangular shapes in the 20 nm size range. While the elliptical particle has only two resonances, a well known fact, we demonstrate that the triangular particle displays a much more complex behaviour with several resonances over a broad wavelength range. Using animations of the field amplitude and field polarization, we investigate the properties of these different resonances. The field distribution ass

The paper presents a new method for the automatic monitoring of bridges deformations. Based on the use of electronic high precision inclinometers, this method permits to accurately reconstruct the deflected shape of the bridge and to follow its long-term evolution. A practical and efficient method for the reconstruction of the deflected shape from measured rotations is proposed. The example of an actual bridge in Western Switzerland, in which the system is operational, is described. The results obtained cor

Combined interferometer and polarimeter systems, using a single detecting element per line of sight, are susceptible to perturbation of the interferometric phase when modulation of the polarization vector is applied. This issue has been investigated extensively for the case of a rotating elliptically polarized probing beam, demonstrating that here a perturbation is inevitable. In this article the analogy between this analysis and earlier work is pointed out, and the underlying physics discussed. It will be

Polarization imaging by use of digital holography

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Fourier Analysis of MAC Polarization

Longitudinal-differential phase distribution near the focus of a high numerical aperture lens: Study of wavefront spacing and Gouy phase

Contribution of Stern layer and membrane polarization to spectral induced polarization of variably saturated sandy soils

Concurrent polarization retrieval in multiheterodyne scanning near-field optical microscopy: validation on silicon formbirefringent grating

Polarization attributes of stimulated Brillouin scattering slow light in fiber

Topological stability of the half-vortices in spinor exciton-polariton condensates

A post-processing pipeline to reconstruct the developing fetal brain using low-resolution MRI

Distributed Representation of Geometrically Correlated Images with Compressed Linear Measurements

A study of polarization effects in metal-ferroelectric-oxide-semiconductor capacitors

Multi-wavelength digital holographic microscopy for sub-micron topography of reflecting specimens

Polarization digital holographic microscope: A single acquisition for a complete determination of polarization state

Tomography using multiple wavelengths in digital holography: Method, simulations and experiments

Complex-Wave Retrieval from a Single Off-Axis Hologram

Method and device for treating signals for detection of stator and rotor errors in magnetic circuits in a synchronous machine

Dimensionally Stable Anode-Type Anode Based on Conductive p-Silicon Substrate

Elastic image registration using parametric deformation models

Bi-directional Photogoniometer for the Assessment of the Luminous Properties of Fenestration Systems

Field polarization and polarization charge distributions in plasmon resonant nanoparticles

Automatic Monitoring of Bridges using Electronic Inclinometers

Analysis of phase measurements in combined interferometer and polarimeter systems