Polarization Properties Of Sample Research Articles

Polarization properties of mouse oocyte captured by Mueller matrix imaging

Non-invasive assessment of oocyte quality is of important basis in embryo transfer and other related fields. Until now, the oocyte quality assessment is mainly focus on the morphology observation. Oocyte quality is often reflected in varieties of its microstructure which can be provided by polarization imaging technology. The Mueller matrix is a label-free technique to characterize all polarization properties of samples. This paper used a Mueller matrix microscope for the first time for non-invasive imaging the mouse oocyte. By Mueller matrix analysis, we successfully examined the dichroism, phase delay and scattering depolarization of oocytes, furthermore used the above to compare the polarization properties of mouse oocytes at GV stage and MII stage and the polarization properties of matured fresh oocytes and postovulatory aged oocytes. In this paper changed phase delay were observed before and after oocyte maturation (and oocyte aging). It suggested that the Mueller matrix imaging may provide a potential breakthrough for oocyte quality assessment.

Mueller-polarimetry of soil and vegetation in the visible I: Depolarization metrics

In this paper the Mueller polarimetry is applied to study the four natural samples in visible (λ = 632.8 nm): soil, sand, clay and moss. To quantify separability of these samples based on their Mueller matrices we analyze their experimental Mueller matrices by calculating a number of single value depolarization metrics (degree of polarization, average degree of polarization, depolarization index, Q(M)-metric) for each sample in in-plane and out-of-plane geometry of experiment. The results obtained show that all depolarization metrics are sensitive to the sample's polarization properties. The most effective identifier is Q(M)-metric in both experimental geometry.

Tolerance analysis of non-depolarizing double-pass polarimetry

Double-pass polarimetry measures the polarization properties of a sample over a range of polar angles and all azimuths. Here, we present a tolerance analysis of all the optical elements in both the calibration and measurement procedures to predict the sensitivities of the double-pass polarimeter. The calibration procedure is described by a Mueller matrix based on the eigenvalue calibration method (ECM) [1]. Our numerical results from the calibration and measurement in the Mueller matrix description with tolerances limited by systematic and stochastic noise from specifications of commercially available hardware components are in good agreement with previous experimental observations. Furthermore, by using the orientation Zernike polynomials (OZP) which are an extension of the Jones matrix formalism, similar to the Zernike polynomials wavefront expansion, the pupil distribution of the polarization properties of non-depolarizing samples under test are expanded. Using polar angles ranging up to 25∘, we predict a sensitivity of 0.5% for diattenuation and 0.3∘ for retardance using the root mean square (RMS) of the corresponding OZP coefficients as a measure of the error. This numerical tool provides an approach for further improving the sensitivities of polarimeters via error budgeting and replacing sensitive components with those having better precision.

Polarization Sensitive Optical Coherence Tomography: A Review of Technology and Applications

Polarization sensitive optical coherence tomography (PS-OCT) is an imaging technique based on light scattering. PS-OCT performs rapid two- and three-dimensional imaging of transparent and translucent samples with micrometer scale resolution. PS-OCT provides image contrast based on the polarization state of backscattered light and has been applied in many biomedical fields as well as in non-medical fields. Thereby, the polarimetric approach enabled imaging with enhanced contrast compared to standard OCT and the quantitative assessment of sample polarization properties. In this article, the basic methodological principles, the state of the art of PS-OCT technologies, and important applications of the technique are reviewed in a concise yet comprehensive way.

Polarization modeling and predictions for Daniel K. Inouye Solar Telescope part 1: telescope and example instrument configurations

We outline polarization performance calculations and predictions for the Daniel K. Inouye Solar Telescope (DKIST) optics and show Mueller matrices for two of the first light instruments. Telescope polarization is due to polarization-dependent mirror reflectivity and rotations between groups of mirrors as the telescope moves in altitude and azimuth. The Zemax optical modeling software has polarization ray-trace capabilities and predicts system performance given a coating prescription. We develop a model coating formula that approximates measured witness sample polarization properties. Estimates show the DKIST telescope Mueller matrix as functions of wavelength, azimuth, elevation, and field angle for the cryogenic near infra-red spectro-polarimeter (CryoNIRSP) and visible spectro-polarimeter. Footprint variation is substantial and shows vignetted field points will have strong polarization effects. We estimate 2% variation of some Mueller matrix elements over the 5-arc min CryoNIRSP field. We validate the Zemax model by showing limiting cases for flat mirrors in collimated and powered designs that compare well with theoretical approximations and are testable with lab ellipsometers.

Towards understanding the detection of profile asymmetry from Mueller matrix differential decomposition

The Mueller matrix differential decomposition is applied to interpret Mueller matrices of asymmetric gratings and to understand the use of Mueller matrix ellipsometry (MME) in distinguishing the direction of profile asymmetry, as reported in our recent work [Chen et al., J. Appl. Phys. 116, 194305 (2014)]. We show that both linear and circular birefringence-dichroism pairs can be extracted from the collected Mueller matrices, which provide a complete description of the sample polarization properties. We present both theoretical and experimental results, which demonstrate that the linear birefringence and dichroism, LB′ and LD′, along the ±45° axes are the origin of the MME in distinguishing the direction of profile asymmetry. We also demonstrate that equal magnitude of profile asymmetry in opposite directions always yields LB′ and LD′ of the same absolute deviation from zero and of opposite sign, when the plane of incidence is no longer perpendicular to grating lines. The sensitivity of LB′ and LD′ to both the magnitude and direction of profile asymmetry is useful in monitoring processes in which symmetric structures are desired.

Optimum selection of input polarization states in determining the sample Mueller matrix: a dual photoelastic polarimeter approach

Dual photoelastic modulator polarimeter systems are widely used for the measurement of light beam polarization, most often described by Stokes vectors, that carry information about an interrogated sample. The sample polarization properties can be described more thoroughly through its Mueller matrix, which can be derived from judiciously chosen input polarization Stokes vectors and correspondingly measured output Stokes vectors. However, several sources of error complicate the construction of a Mueller matrix from the measured Stokes vectors. Here we present a general formalism to examine these sources of error and their effects on the derived Mueller matrix, and identify the optimal input polarization states to minimize their effects in a dual photoelastic modulator polarimeter configuration. The input Stokes vector states leading to the most robust Mueller matrix determination are shown to form Platonic solids in the Poincaré sphere space; we also identify the optimal 3D orientation of these solids for error minimization.

Polarization sensitive optical coherence tomography of melanin provides intrinsic contrast based on depolarization

Polarization sensitive optical coherence tomography (PS-OCT) is a functional extension of OCT. In addition to imaging based on tissue reflectivity, PS-OCT also enables depth-resolved mapping of sample polarization properties such as phase-retardation, birefringent axis orientation, Stokes vectors, and degree of polarization uniformity (DOPU). In this study, PS-OCT was used to investigate the polarization properties of melanin. In-vitro measurements in samples with varying melanin concentrations revealed polarization scrambling, i.e. depolarization of backscattered light. Polarization scrambling in the PS-OCT images was more pronounced for higher melanin concentrations and correlated with the concentration of the melanin granules in the phantoms. Moreover, in-vivo PS-OCT was performed in the retinas of normal subjects and individuals with albinism. Unlike in the normal eye, polarization scrambling in the retinal pigment epithelium (RPE) was less pronounced or even not observable in PS-OCT images of albinos. These results indicate that the depolarizing appearance of pigmented structures like, for instance, the RPE is likely to be caused by the melanin granules contained in these cells.

Polarization properties of InAs/InGaAsP/InP quantum dot stacks

Surface and edge emission polarization properties of samples containing four InAs/InGaAsP/InP quantum dot layers with a stacking period from 30 nm down to 5.1 nm are investigated. Closely stacked layers show decreasing (constant) edge emission degree of polarization for emission perpendicular to the short dot (long dot) axis. Increase of the surface emission degree of polarization with decreasing period suggests an elongation of the wavefunction as dot period decreases. Use of a miscut substrate eliminates this surface emission polarization dependence, which could lead to edge polarization-independent applications.