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Electromagnetically induced Gain-phase grating in a double Vtypequantum system

Ali Mortezapour and amir hossein ranjbar

Doc ID: 347516 Received 05 Oct 2018; Accepted 18 Feb 2019; Posted 19 Feb 2019  View: PDF

Abstract: Finding schemes to promote the efficiency of phase gating nowadays is a main concern. Weaddress this issue by devising a feasible and innovative scheme which enables us to obtain again-phase grating. It is shown that a linearly polarized probe field travelling through adouble V–type closed-loop atomic system, which is driven by a standing wave and amicrowave field, can be efficiently diffracted in higher orders. As a significant result, wefind that intensity of the diffracted field is highly amplified in every single order-directioncompared with the intensity of input probe field. The responsible mechanism is induced gainaccompanied by the large dispersion arising due to the applying microwave field. It is shownthat in the presence of microwave field, among various parameters, the relative phase of theapplied fields has the most appreciable effect on enhancing the intensity of diffractionorders. It is also demonstrated that quantum interference between decay channels of thequantum system can be used as a tool to manipulate the intensity of diffraction orders.

Spatial modifications of a Gaussian beam incident on a diffraction grating at microwave frequencies

Xiaodong Wang, Bryan Fox, and Ronald Vernon

Doc ID: 352483 Received 23 Nov 2018; Accepted 18 Feb 2019; Posted 19 Feb 2019  View: PDF

Abstract: When a fundamental Gaussian beam at microwave frequency is incident on a reflection grating, there are spatial modifications such as a lateral shift for the reflected and diffracted beam and generation of higher order Gaussian modes. Different parameters of the incident beam such as waist radius, beam frequency, incident angle and polarization direction affect the spatial modifications differently. We trace the beam propagation and central ray position by simulation and find how these parameters influence the beam modifications.

Measurement of the diffusion of light within paper

Geoffrey Rogers, Olympe Corblet, Thierry Fournel, and Mathieu Hébert

Doc ID: 356884 Received 07 Jan 2019; Accepted 18 Feb 2019; Posted 19 Feb 2019  View: PDF

Abstract: The diffusion of light within paper has an affect on the colors in a halftone image, and must be takeninto consideration in modeling halftone color. The diffusion can be accounted for by using the pointspread function, or equivalently the modulation transfer function (MTF) of the paper. A novel methodof measurement of paper MTF, called the bar-target series expansion method, is proposed here. Theexperimental results of the method confirm that the shape of the MTF is an exponential function, whichcorresponds to a Lorentzian line spread function as predicted by the multiple-path model of reflection.

Beam-wander analysis in turbulent ocean withthe effect of the eddy diffusivity ratio and theouter scale

Peng Yue, Xiaohui Luan, Yi Xiang, Zongmin Cui, and Mengjie Wu

Doc ID: 352383 Received 20 Nov 2018; Accepted 15 Feb 2019; Posted 19 Feb 2019  View: PDF

Abstract: In this paper, we theoretically analyze the beam wander variance for the Gaussianbeam propagation through weak oceanic turbulence. Particularly, we consider the effect of theeddy diffusivity ratio of salinity to temperature as well as the outer scale on the beam wander. Toget to the tractable theoretical results, we first develop an approximate oceanic refractive-indexspectrum with the outer scale and variable eddy diffusivity ratio. Based on this spectrum in weakturbulence, we then derive the closed-form expression for the beam wander variance. We presentnumerical results to show that the beam wander is either overestimated or underestimated ascompared to the previous analyses which set the eddy diffusivity ratio to one. Besides, the finiteouter scale of turbulence can significantly reduce the beam wander for Gaussian beams.

The vector space of generalized radii ofellipses for quantitative analysis of blurpatches and other referred apertures in theastigmatic eye

Tanya Evans and William Harris

Doc ID: 349368 Received 29 Oct 2018; Accepted 14 Feb 2019; Posted 19 Feb 2019  View: PDF

Abstract: Ellipses are features of several structures in astigmatic eyes; they include retinalblur patches. How can one calculate change or averages or perform other quantitative analyses on such elliptical structures? The matrix A in the equation rTAr = 1, commonly used to represent an ellipse, is positive definite; such matrices do not define vector spaces. They are unsuitable, therefore, for quantitative analysis of ellipses. This paper defines a generalized radius R of an ellipse that is positive or negative definite for locally diverging or converging rays respectively, indefinite between line foci and singular at foci. Generalized radii of ellipses constitute a vector space and are suitable for quantitative analysis of ellipticalocular structures.

Psychophysical study of the optical origin of starbursts

Renfeng Xu, Larry Thibos, Norberto Lopez-Gil, Pete S. Kollbaum, and Arthur Bradley

Doc ID: 351961 Received 14 Nov 2018; Accepted 14 Feb 2019; Posted 14 Feb 2019  View: PDF

Abstract: Starbursts seen around small bright lights at night have been attributed to optical scatter, diffraction oraberrations. We manipulated pupil aperture and aberrations to investigate the entopic appearance of perceivedstarbursts. The impact of circular, annular, and wedge-shaped pupil apertures, and spherical aberration sign andmagnitude were used to identify pupil sub-apertures responsible for each radial perceived starburst line. Localintensity distributions within the starbursts mapped onto unique sub-regions of the pupil of both phakic andpseudophakic eyes, consistent with the hypothesis that ocular aberrations are the cause of starbursts. In paraxiallyfocused eyes, the size of starbursts is predicted by the amount of spherical aberration, and starburst orientation iseither the same or 180 degree rotated from the pupil region that creates each starburst line. No starbursts are seenwhen the pupil diameter is smaller than 3mm. Replacing the eye’s natural lens with a radially symmetric andoptically homogeneous intraocular lens reduced the observed number of starbursts by 50%. Geometrical opticsmodeling including the measured aberrations of an individual eye can reveal PSF structure that captures some ofthe key elements of the entopic perceptions.

Spatial intensity correlations of a vortex beam and aperfect optical vortex beam.

CRISTIAN ACEVEDO, Yezid Torres, and Aristide Dogariu

Doc ID: 353271 Received 03 Dec 2018; Accepted 12 Feb 2019; Posted 13 Feb 2019  View: PDF

Abstract: We present model based on the Fresnel diffraction scheme for the spatial coherence function of random fieldscreated by scattering optical vortex and perfect vortex beams. By using the spatial coherence function we showedanalytically, numerically and experimentally the dependence and independence of the speckle size of an opticalvortex and perfect optical vortex with the topological charge, respectively, also we showed in both cases the lineardependence of speckle size with the distance of propagation. Furthermore, we describe a regime in where thespatial coherence function is non-evolving for the optical vortex beam and perfect optical vortex beams with thepropagation distance.

Derivation and application of a Green functionpropagator suitable for nonparaxial propagation overa two dimensional domain

David Capps

Doc ID: 347791 Received 09 Oct 2018; Accepted 09 Feb 2019; Posted 11 Feb 2019  View: PDF

Abstract: The goal of optical simulation is to determine the performance characteristics of an optical system from aknowledge of its physical construction and how it affects light sent through it. To produce meaningful resultsefficiently, two simulation approaches are available for passing light through a system, geometrical raytracing andwave optics. Within the wave optics realm, there are many techniques for determining the optical fields within asystem, both numerical and analytical. A few of the numerical techniques are finite difference, finite element, andFFT based; analytical techniques include modal expansions, coupled wave theory, series expansions, and Greenfunction propagators. A propagator is a function which gives the light fields at any specified location if they areknown at a source location; this is possible because the light fields, electric and magnetic, satisfy a differentialequation, in the case of time harmonic fields, the Helmholtz equation. The propagator is a transfer function for thefields and often takes the form of an integral; in which case, the integrand is a product of the transfer function withthe source field distribution, and the integration is performed over the source field coordinates. The integrandtransfer function, also known as a Green function or propagation kernel, is a solution of the Helmholtz equation.An approximation is often used in finding a solution to the Helmholtz equation, called the paraxial approximation,in which the second derivative in the propagation direction is dropped. If no approximation is made, and allsecond derivatives are kept, the solution is nonparaxial. In the present paper, a Green function for the propagatorof the Helmholtz equation over two dimensional domains is derived, differing in functional form from previouswork on 2D propagation. An angular spectrum integral is evaluated and the resulting Green function, thepropagator kernel, is a nonparaxial analytic solution of the Helmholtz equation. The propagator could be applieddirectly to the electric and magnetic field components, instead, it is applied to the Hertz vector components. TheHertz vector is a potential function, similar to the vector potential, defined such that the electric and magneticfields are found by taking derivatives of it. An advantage of the Hertz vector is that only it need be propagated,versus two, electric and magnetic, vectors. In this paper, the derived propagator is applied to Hertz vectorcomponents defined by Legendre polynomial expansions, and derivatives are taken of the propagated Hertz vectorcomponents to calculate the associated electric and magnetic fields. The Green function propagator and all fieldquantities produced by its application are closed form analytic expressions.

Average biometry of the cornea in a large populationof Iranian school children

Rafael Navarro, Jos Rozema, MOHAMMAD EMAMIAN, Hassan Hashemi, and Akbar Fotouhi

Doc ID: 351517 Received 14 Nov 2018; Accepted 07 Feb 2019; Posted 07 Feb 2019  View: PDF

Abstract: This work establishes the average Scheimpflug corneal tomography for a population of 4953 healthy Iranianprimary school children. These data were transformed to determine the corneal position and orientation in 3–dimensional space, followed by a model fit that combines a biconic with a Zernike expansion. Girls were found tohave slightly steeper corneas than boys. Both corneal surfaces show negative conic constants and significanthigher–order aspheric Zernike terms. The corneal surfaces are decentered and misaligned with respect to eachother and to the line of sight. Consequently, the average corneal surfaces may be considered as decentered andmisaligned higher–order aspheres.

Contrast adaptation appears independent from thelongitudinal chromatic aberration of the human eye

Caroline Kraft, Alexander Leube, Arne Ohlendorf, and Siegfried Wahl

Doc ID: 348435 Received 16 Oct 2018; Accepted 06 Feb 2019; Posted 07 Feb 2019  View: PDF

Abstract: As ocular chromatic aberration was suspected to cue contrast adaptation in human vision, the purpose ofthis study was to investigate contrast adaptation under monochromatic light conditions. A single and acomplex frequencies adaptation stimulus were used and monochromatic conditions were achieved usingband pass filters with short (4702 nm), medium (5302 nm) and long (6302 nm) transmission wavelengths.Post-adaptational contrast sensitivity was shown to be significant decreased for all wavelengthconditions for the single frequency stimulus. A significant differences of contrast adaptation betweenshort and long wavelength was found. Consistently, adaptation led to a significant decrease in contrastsensitivity for the complex frequency stimulus. To conclude, contrast adaption under mesopic illuminationoccur independent from the longitudinal chromatic aberration of the eye, it can be inferred that thismechanism can be used to distinguish between the sign of optical defocus in poly- and monochromaticlight conditions.

Application of 2D intensity maps in high accuracypolarimetry

Mykola Shopa and Nazar Ftomyn

Doc ID: 342828 Received 22 Aug 2018; Accepted 05 Feb 2019; Posted 05 Feb 2019  View: PDF

Abstract: We propose the analysis of the 2D intensity contours maps which is based on the optical transmission function forthe polarizer-specimen-analyzer system. The small modification of HAUP technique (high-accuracy universalpolarimeter) was used to measure the intensity maps (HAUP maps), determine the phase retardation, lineardichroism (LD) parameters and multiple light reflection contribution in uniaxial crystals. We have performedmeasurements in direction perpendicular to the optical axis on pure birefringent LiNbO3, birefringent opticallyactive SiO2 and two birefringent optically active dichroic galogermanate crystals doped with Mn3+ and Cr3+ ions. Wehave obtained good agreement of the experimental data for 532, 633 and 650 nm wavelengths with analyticalvalues. These results extend the capabilities of the high-accuracy polarimetry to the anisotropic crystal studies.

Parametric Effects on the Evaluation ofThreshold Chromaticity Differences using RedPrinted Samples

Fernando Brusola, Ignacio Montañana, Begoña Jorda, and Manuel Melgosa

Doc ID: 349845 Received 01 Nov 2018; Accepted 03 Feb 2019; Posted 04 Feb 2019  View: PDF

Abstract: Results from different authors showed deviations of radial orientation in a*-b*plane (tilt) for the major axes of chromaticity-discrimination ellipses centered around the CIEred color center [A.R. Robertson, Color Res. Appl. 3, 149 (1978)], which are not consideredby most of the current advanced color-difference formulae (e.g., CIEDE2000). We performeda visual experiment using red printed samples in order to test the influence of the separationbetween samples (gap) on the mentioned tilt. Our results confirm a counter-clockwise tilt offitted a*-b* ellipses with a magnitude of approximately 36° for samples with no separation,which is similar to that detected by other authors, and a reduction of the mentioned tilt owingto the separation of the samples. We detected a tilt of approximately 22° for samples with ablack gap of 0.5 mm and a tilt of approximately 25° for samples with a white gap of 3 mm.Notably, the uncertainty of previous values given by the corresponding credibility intervals of95% posterior probability is approximately ±8° of the mean values. Finally, we study theperformance of the most widely used color-difference formulae in graphic arts sector usingour current experimental results, and conclude that the performance of the CAM02-SCD andCAM02-UCS color-difference formulae is significantly better than that of the CIEDE2000formula.

Circular gradient-diameter photonic crystal fiberwith large mode area and low bending loss

Junlong Han, Exian Liu, and Jianjun Liu

Doc ID: 345368 Received 07 Sep 2018; Accepted 02 Feb 2019; Posted 04 Feb 2019  View: PDF

Abstract: In this paper, a silica-based six-fold circular gradient-diameter photonic crystal fiber (CGPCF) with five rings isproposed and the matching conditions of air hole lattices are established considering the gradient and diameter ofair holes. This CGPCF supports endlessly single-mode propagation due to the existence of small air holes near tofiber core based on the matching rule. Simultaneously, it exhibits ultra-large effective mode area of 3110 μm2 in thestraight case and 1105 μm2 in the bending case with bending radius of 15 cm at the wavelength of 1550 nm. Inaddition, within an ultra-wide communication wavelength range from 1000 nm to 2000 nm (from 1350 nm to 2000nm), the effective mode area in the straight (bending) case still maintains more than 3043 μm2 (981 μm2) and thebending loss maintains an ultra-low order of magnitude of 10-4 dB/m at a great degree of bending radius of 15 cm.Moreover, the rotation-symmetric structure of CGPCF can reduce the impact of bending orientation on the opticalproperties. The proposed CGPCF is highly meaningful for optical fiber communication, high-power laser systemsand optical amplifiers.

Quantitative model of the image of a radiating dipolethrough a microscope

samira khadir, Patrick Chaumet, Guillaume Baffou, and Anne Sentenac

Doc ID: 352169 Received 23 Nov 2018; Accepted 01 Feb 2019; Posted 04 Feb 2019  View: PDF

Abstract: In this article, we introduce a formalism to determinethe relationship between the full vectorial electric fieldexisting at the object plane of a microscope and thatexisting at the image plane. The model is then usedto quantitatively simulate, both in phase and intensity,the image of a radiating electric dipole either placedin a homogeneous medium or in the vicinity of a substrate.These simulations are compared with experimentalmeasurements on single gold nanoparticles carriedout by quadriwave lateral shearing interferometry.

Channel capacity of OAM based wireless communicationsystems with partially coherent elegant Laguerre-Gaussian beams in oceanic turbulence

Yongxu Li, zhiwei cui, Yiping Han, and Yuanfei Hui

Doc ID: 348351 Received 16 Oct 2018; Accepted 30 Jan 2019; Posted 31 Jan 2019  View: PDF

Abstract: For practical wireless communication links, one of the critical challenges is the random fluctuation of turbulencethat will impair link performance. Here a transmission model of partially coherent elegant Laguerre-Gaussian (ELG)beams in oceanic turbulence is established. Analytical formula for channel capacity of a partially coherent ELGbeam propagating through turbulent ocean is derived. Effects of oceanic turbulence on the evolution of channelcapacity performance are studied quantitatively in a series of numerical simulations. Research results show thatdecreasing the rate of dissipation of mean-square temperature, ratio of temperature to salinity, as well asincreasing the dissipation rate of turbulent kinetic energy per unit mass of fluid of turbulent ocean can significantlyimprove communication channel capacity. Furthermore, choosing optimum beam source parameters are favorableto mitigate the influence of oceanic turbulence. Results also show that in the underwater turbulence, the partiallycoherent ELG beams are more affected by turbulence as compared to the fully coherent ELG beams. These studyresults may provide potential helpful in designing the free-space optical vortex communication systems.

Quaternion algebra for Stokes-Mueller formalism

Ertan Kuntman, mehmet kuntman, Adolfo Canillas, and Oriol Arteaga

Doc ID: 355271 Received 13 Dec 2018; Accepted 29 Jan 2019; Posted 31 Jan 2019  View: PDF

Abstract: We show that the Stokes-Mueller formalism can be reformulated in terms of quaternions, and the quaternion algebra is a suitable alternative presentation of the formalism of Mueller-Jones states that we have recently described [J. Opt. Soc. Am. A 34, 80-86 (2017)]. The vector and matrix states associated with the Mueller matrices of nondepolarizing optical systems are different representations isomorphic to the same quaternion state, and this quaternion state turns out to be the rotator of the Stokes quaternion. In this work we study the properties of this general quaternion state and its application to the calculus of polarization effects. We also show that the coherent linear combination of nondepolarizing optical media states and depolarization phenomena can be reformulated in terms of quaternion states.

Effect of oceanic turbulence on the visibility of underwater ghost imaging

Yong-jian Gu, qinwei zhang, Wen-Dong Li, Kai Liu, Longwen Zhou, and zhaoming Wang

Doc ID: 351588 Received 09 Nov 2018; Accepted 29 Jan 2019; Posted 29 Jan 2019  View: PDF

Abstract: We carry out a detailed study on underwater ghost imaging in oceanic turbulence. Theoretically, we obtain expressions for the impulse response function and visibility of ghost imaging in oceanic turbulence based on the power spectrum of turbulence and the extended Huygens-Fresnel integral. Numerically, we investigate the visibility of ghost imaging under various turbulence conditions and over different propagation distance. We find that in weak oceanic turbulence, the ghost imaging could maintain its qualityover as long as tens of meters, whereas in strong oceanic turbulence, the ghost imaging is only available in much shorter distance. These results provide guidance for the realization of adaptive underwater optical ghost imaging over different length scales under the effect of oceanic turbulence.

Data analysis of the Ocular ResponseAnalyzer for improved distinction anddetection of glaucoma

Magdalena Asejczyk-Widlicka, Agnieszka Jóźwik, Henryk Kasprzak, Marcelina Sobczak, and Barbara Pierscionek

Doc ID: 351103 Received 06 Nov 2018; Accepted 28 Jan 2019; Posted 28 Jan 2019  View: PDF

Abstract: The purpose of the study was to evaluate the clinical utility of the output parameters of OcularResponse Analyzer (ORA) and those calculated from the raw ORA in healthy eyes andglaucoma suspects, and patients with two types of glaucoma.The raw ORA data were analysed using custom software that included Gaussian filtering ofapplanation curves for three different window sizes.Findings presents a novel means of optimising usage of measurements from the OcularResponse Analyser that can refine the characteristics of corneal biomechanics and provide adistinction between types of glaucoma and an improvement in diagnosis and early detection.

Full-Spectrum Denoising of High-SNR Hyperspectral Images

Miguel Colom and Jean-Michel Morel

Doc ID: 348361 Received 16 Oct 2018; Accepted 28 Jan 2019; Posted 29 Jan 2019  View: PDF

Abstract: The high spectral redundancy of hyper/ultraspectral imaging raises three challenges: a) to design accurate blind noise estimation methods, b) to denoise images with very high SNR, and c) to secure unbiased denoising. We solve (a) by a new blind noise estimation (b) by a novel Bayesian algorithm exploiting spectral redundancy and spectral clustering, and (c) by accurate measurements of the interchannel correlation after denoising. We demonstrate the effectiveness of our method on two ultraspectral Earth imagers, IASI and IASI-NG, one flying and the other in project, and sketch the major improvement in instrument resolution entailed by such unbiased denoising.

Spectral behavior of light waves on scattering froma semi-soft-boundary medium with spectraldependence

Zhenfei Jiang, Zhiru Huang, Ke Cheng, and Tao Wang

Doc ID: 348951 Received 23 Oct 2018; Accepted 27 Jan 2019; Posted 28 Jan 2019  View: PDF

Abstract: The far-zone behavior of polychromatic light waves on scattering from an isotropicsemi-soft-boundary medium with spectral dependence is considered, and both spectral shifts andspectral switches of the scattered field have been discussed. It is shown that the spectral behavior of thefar-zone scattered field is influenced by the structural function width of the dielectric susceptibility ofthe scattering medium. In particular, the structural function width of the dielectric susceptibility of thescattering medium plays an important role in the direction at which the spectral switch occurs. Theseresults may have potential applications in areas such as the inverse scattering problem.

A hand-held aperture sharing camera for a Multiview image set

Jung-Young Son, Jaesoon Kim, Do-Hyung Kim, Hyoung Lee, and Sumio Yano

Doc ID: 342979 Received 22 Aug 2018; Accepted 24 Jan 2019; Posted 25 Jan 2019  View: PDF

Abstract: A hand-held camera which is capable of acquiring full parallax multiview images is introduced. Since the camera is based on spatial sharing of the aperture stop of a digital camera, it is easy to manufacture. The aperture stop is spatially shared by a 2-D high speed LC shutter array which is fixed on the front surface of the camera objective. The shutter array consists of 8 x 8 .LC shutters to acquire 8 x 8 multiview images. The equivalent optical configuration of the camera is not different from that of a parallel-type multiview camera array. Each of the multiview images has an equal disparity from its neighbors and has the full detector resolution of the camera. The disparity is small enough to be used in Light field imaging. The depth resolution and the resolvable number of depth layers calculated from the configuration are not different from those obtained experimentally.

Defocus optical transfer function: fast evaluation andlightweight storage based on cubic spline interpolation

Stanislav Budzinskiy and Alexander Razgulin

Doc ID: 346623 Received 24 Sep 2018; Accepted 24 Jan 2019; Posted 25 Jan 2019  View: PDF

Abstract: Certain problems of image processing and 3D optical sectioning require the knowledge of defocus opticaltransfer function (OTF) with high resolution but its computation is not trivial: the OTF is an oscillatoryintegral. To efficiently compute the defocus OTF of a linear isoplanatic imaging system in incoherentillumination with a given accuracy on a fine grid, we suggest to use cubic spline interpolation. Theapproximation error analysis of the splines shows that our method requires fewer OTF point-evaluationsthan the direct evaluation at each grid point. The cubic spline can also be seen as a compact representationof the OTF and can be used to resolve data transfer bottlenecks and lack of storage difficulties.

Defocus vibrations in optical systems –considerations in reference to the human eye

Maciej Bartuzel, D. Robert Iskander, Ivan Marin-Franch, and Norberto Lopez-Gil

Doc ID: 346684 Received 25 Sep 2018; Accepted 24 Jan 2019; Posted 25 Jan 2019  View: PDF

Abstract: Experimental visual acuity (VA) of eight subjects were measured using FreiburgVision Test in a custom-made adaptive optics system. Measurements were conducted under acontrol and five defocus induced conditions. In the defocused induced conditions 1 D ofmyopic defocus was added to the system using Badal stage and defocus vibrations with fivedifferent levels of amplitude were generated by a deformable mirror at 50 Hz. Computationalsimulations of visual Strehl ratio (VSOTF) were performed using average aberrations of eachsubject recorded in the control condition. For the first time, it is shown experimentally thatboth simulated VSOTF and experimentally measured VA improve when defocus vibrationsare added to a defocused eye.

Computational simulation of human perception ofspatially-dependent patterns modulated by degreeand angle of linear polarization

Gary Misson, Shelby Temple, and Stephen Anderson

Doc ID: 349663 Received 31 Oct 2018; Accepted 23 Jan 2019; Posted 23 Jan 2019  View: PDF

Abstract: Recent studies on polarization perception have shown that humans are sensitive to patterned stimuli modulatedby either angle of linear polarization (AoP) or degree of polarization (DoP). Here, we present a model of humanpolarization sensitivity that incorporates both AoP and DoP as spatially-dependent input variables. Applying themodel to both sinusoidal and square-wave modulated DoP and AoP inputs, we demonstrated the theoreticalsimilarities and differences generated by such inputs. Our model indicates: (i) edge boundaries between twoadjacent areas of different linear polarization are preserved for both AoP and DoP modulated stimuli; and (ii)compared with DoP stimuli, AoP stimuli generate greater luminance changes at the photoreceptor level, suggestingthat AoP modulated patterns are potentially more salient than DoP patterns. The computational model wassupported experimentally with an optical test of the model comprising a radial diattenuating polarizing filter andmodified liquid crystal displays (LCD) generating DoP and AoP modulated outputs. Psychophysical measures ofhuman sensitivity confirmed the increased salience of AoP relative to DoP modulated stimuli. These findings havepractical application to the selection of DoP and AoP modulated stimuli for the investigation of macular functionand macular pigment density in healthy and diseased eyes.

Complete Mueller matrix from a partialpolarimetry experiment: the nine-element case

Razvigor Ossikovski and Oriol Arteaga

Doc ID: 346473 Received 20 Sep 2018; Accepted 22 Jan 2019; Posted 23 Jan 2019  View: PDF

Abstract: We show that an incomplete, nine-element Mueller matrix with a row and acolumn missing, obtained in a partial polarimetry experiment can be completed to a full,sixteen-element Mueller matrix, provided depolarization is absent experimentally. There existexactly two solutions for the missing row and column, differing from one another only by thesigns of the respective row and column elements. To select the correct solution, additionalinformation on the sample properties, such as weak anisotropy or special symmetry, isneeded. We provide analytical and numerical procedures for completing the partial Muellermatrix for the cases of practical interest and illustrate the approach on an experimentalexample.

Study on angular distribution of dierential photoacoustic cross-section and itsimplication in source size determination

Anuj Kaushik, Deepak Sonker, and Ratan Saha

Doc ID: 352520 Received 21 Nov 2018; Accepted 21 Jan 2019; Posted 22 Jan 2019  View: PDF

Abstract: Angular distribution of dierential photoacoustic cross-section (DPACS) has been exam-ined for various nonspherical axisymmetric particles. The DPACS as a function measurementangle has been computed for spheroidal particles with varying aspect ratio and fitted withtri-axes ellipsoid form factor model to extract shape parameters. Similar study has beencarried out for normal and pathological red blood cells and fitting has been performed withthe tri-axes ellipsoid and finite cylinder form factor models to evaluate cellular morphology.It is found that an enhancement of the DPACS occurs as the surface area of the photoacous-tic source normal to the direction of measurement is increased. It decreases as the thicknessof the source along the same direction increases. For example, the DPACS for normal ery-throcyte along the direction of symmetry is nearly 20 times greater than a pathological cell.Further, the first minimum appears slightly latter ( 4) for healthy cell compared to thatof a diseased cell. Shape information of spheroids can be precisely estimated by the firstmodel. Both the models provide accurate estimates of shape parameters for normal redblood cell (errors within 4%). It may be possible to assess cellular morphology from angularprofile of the DPACS using form factor models.

On the geometry of visual starbursts

Jacob Rubinstein

Doc ID: 349115 Received 24 Oct 2018; Accepted 18 Jan 2019; Posted 22 Jan 2019  View: PDF

Abstract: The patterns observed by people when they look at stars are collectively called starbursts. Similar patterns are observed when viewing any distant object with sufficiently large pupils. We show here that starbursts are mainly the intersections of the caustic surfaces of the eye's optics field with the retina. In particular we derive the equations governing these caustic curves, present a few properties of their solutions, and compare the solutions with recent clinical observations. We further classify the starbursts into primary (the caustic curves themselves) and secondary (the diffraction patterns near the caustics).

Hyperspectral imaging in color vision research:Tutorial

David Foster and Kinjiro Amano

Doc ID: 347289 Received 01 Oct 2018; Accepted 11 Jan 2019; Posted 15 Jan 2019  View: PDF

Abstract: This tutorial offers an introduction to terrestrial and close-range hyperspectral imaging and some of its uses inhuman color vision research. The main types of hyperspectral cameras are described together with proceduresfor image acquisition, postprocessing, and calibration for either radiance or reflectance data. Imagetransformations are defined for colorimetric representations, color rendering, and cone receptor andpostreceptor coding. Several example applications are also presented. These include calculating the colorproperties of scenes, such as gamut volume and metamerism, and analyzing the utility of color in observertasks, such as identifying surfaces under illuminant changes. The effects of noise and uncertainty areconsidered both in image acquisition and in color vision applications.

Complete Mueller matrix from a partialpolarimetry experiment: the twelve-elementcase

Oriol Arteaga and Razvigor Ossikovski

Doc ID: 349767 Received 31 Oct 2018; Accepted 08 Jan 2019; Posted 08 Jan 2019  View: PDF

Abstract: Conventional generalized ellipsometry instrumentation is capable of measuringtwelve out of the sixteen elements of the Mueller matrix of the sample. The missing column(or row) of the experimental partial Mueller matrix can be analytically determined underadditional assumptions. We identify the conditions necessary for completing the partialMueller matrix to a full one. More specifically, such a completion is always possible if thesample is nondepolarizing; the fulfilment of additional conditions, such as the Mueller matrixexhibiting symmetries or being of special two-component structure, are necessary if thesample is depolarizing. We report both algebraic and numerical procedures for completing thepartial twelve-element Mueller matrix in all tractable cases and validate them on experimentalexamples.

High resolution augmented reality 3D display withuse of lenticular lens array holographic opticalelement

Huan Deng, Cong Chen, Min-Yang He, Jiao-Jiao Li, Han-Le Zhang, and Qiong-Hua Wang

Doc ID: 351354 Received 08 Nov 2018; Accepted 07 Jan 2019; Posted 09 Jan 2019  View: PDF

Abstract: An augmented reality (AR) three-dimensional (3D) display based on one-dimensional integralimaging (1DII) by using a lenticular lens array holographic optical element (LLA-HOE) is proposed.The 3D image of the 1DII has higher vertical resolution compared with that of the conventionalintegral imaging (II) whose resolution is sharply reduced for providing quasi-continuous viewpointsin both the horizontal and vertical directions. The proposed 3D display consists of a projector and anLLA-HOE and it is compact. As an image combiner, the LLA-HOE can diffract the Bragg matchedlight rays that has the same wavelength and incident angle as the original reference wave and it canfunction as a lenticular lens array to reconstruct 3D image but transmit the other light rays emittedfrom the surroundings. In the experiment, an 80×80mm sized LLA-HOE is recorded, and acombination of a high resolution 3D virtual image and a real 3D object is presented by the proposedAR 3D display.

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