Accepted papers to appear in an upcoming issue
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Calculation of light scattering of an elliptical Gaussianbeam by a spherical particle
Jianqi Shen, Xiang Liu, wei wang, and Haitao Yu
Doc ID: 325122 Received 28 Feb 2018; Accepted 18 Jun 2018; Posted 18 Jun 2018 View: PDF
Abstract: The use of elliptical Gaussian beam (EGB) for applications relying on light scattering depends much on the ability toevaluate the beam shape coefficients (BSC) effectively and accurately. Based on the angular spectrumdecomposition (ASD) of the radial components of the beam field, we present the formulations of the BSCs for theEGB. Numerical calculations of the BSCs, the beam reconstruction and light scattering are performed. The fidelity ofthe reconstructed field to the given one is discussed so as to examine the BSC calculation. A comparison of the ASDmethod with the quadrature and localized approximation (LA) methods leads to the conclusion that the ASDmethod is much faster than the quadrature method, and it is very powerful for acquiring reliable and accurateresults of BSCs, even for far off-axis locations and high ellipticities of the EGB.
Propagation and dynamical characteristics of Bessel-Gaussian beam in a chiral medium
zhiwei cui, Yuanfei Hui, Yongxu Li, Wenjuan Zhao, and Yiping Han
Doc ID: 332421 Received 24 May 2018; Accepted 18 Jun 2018; Posted 18 Jun 2018 View: PDF
Abstract: Based on the ABCD transfer matrix and Collins formula, the analytical expressions of the complex amplitude of theBessel-Gaussian beam in a chiral medium are derived. By introducing vector potential in the Lorentz gauge, theelectromagnetic field components of the Bessel-Gaussian beam are determined under the paraxial approximation.Through numerical calculations, the propagation of the Bessel-Gaussian beam in a chiral medium is examined.Results show that Bessel-Gaussian beams split into the left circularly polarized beam and the right circularlypolarized beam with different propagation trajectories. And the propagation trajectory of the Bessel-Gaussianbeam can be controlled by varying half-cone angle of the Bessel-Gaussian beam and the chiral parameter of themedium. The dynamical characteristics, including the energy, momentum, spin, and orbital angular momentum, ofBessel-Gaussian beams in a chiral medium are also simulated and discussed in detail. The results would be muchhelpful to understand the interaction mechanism between the structured light beams and chiral medium.
Array tilt in the atmosphere and its effect on opticalphased array performance
Doc ID: 325984 Received 13 Mar 2018; Accepted 18 Jun 2018; Posted 19 Jun 2018 View: PDF
Abstract: This paper investigates atmospheric array tilt and its effect on target-in-the-loop optical phased array(OPA) performance. Assuming a direct-solve, piston-only-phase-compensation OPA, two expressions forthe atmospheric array tilt variance are derived using Mellin transform techniques. The first—the “full”array tilt variance—is germane when the OPA is sensitive to atmospheric tilt and is shown to significantlyimpact OPA target-plane intensity. The second—the Zernike-tilt-removed array tilt variance—is relevantwhen a separate system compensates for atmospheric tilt (the more likely scenario) and is shown to negligiblyaffect OPA performance. To show how atmospheric array tilt errors affect target-plane intensity,moments of the far-zone (or focused) array intensity, as functions of the array tilt variance, are derivedand discussed. Lastly, Monte Carlo simulation results are presented to validate the theoretical array tiltvariance expressions.
Parabolic-Gaussian Schell-model sources and their propagations
Li Wang, ADEEL ABBAS, Jisen Wen, and Chenni Xu
Doc ID: 328542 Received 17 Apr 2018; Accepted 17 Jun 2018; Posted 18 Jun 2018 View: PDF
Abstract: In this work, a new class of partially coherent Schell-type sources is introduced by modifying its degree of coherence, which is a product of a parabolic function and a Gaussian function. Such sources are confirmed to be physically genuine and may be called as parabolic-Gaussian Schell-model (PGSM) sources. The propagating expression of the cross-spectral density function of such PGSM sources are derived in a general linear optical system. Especially, the propagation properties of such PGSM beams in both free space and lens systems are discussed. It shows that such PGSM sources can produce dark-hollow intensity profiles in the regions of free space very near as well as far away from the source plane, or in the focal region of the lens system.
Goos-Hänchen and Imbert-Fedorov shifts ofhigher-order Laguerre-Gaussian beamsreflected from a dielectric slab
Konstantin Pichugin, Dmitrii Maksimov, and Almas Sadreev
Doc ID: 327598 Received 04 Apr 2018; Accepted 14 Jun 2018; Posted 14 Jun 2018 View: PDF
Abstract: We consider reflection of the Laguerre-Gaussian light beams by a dielectric slab. Ina view of the unified operator approach the higher-order Laguerre-Gaussian beams represent aparametric family with the transverse beam profile given by an arbitrary generating parameter.Relaying on the Fourier expansion in the focal plane of the beam we compute the Goos-Hänchenand the Imbert-Fedorov shifts for light beams with non-zero order and azimuthal index. It isdemonstrated that the both shifts exhibit resonant behavior as functions of the angle of incidencedue to the interference between the waves reflected from the upper and lower interfaces. Thecentroid shifts strongly depend on the order and azimuthal index of the beam. Most interestingly,it is found that the generating parameter of the higher-order beam families strongly affects theshifts. Thus, reshaping of the incident wavefront with fixed order and azimuthal index changesthe linear Goos-Hänchen shift up to one half of the beam radius, both negative and positive.
Fast Iterative Tomographic Wave-front Estimation withRecursive Toeplitz Reconstructor Structure for LargeScale Systems
Yoshito Ono, Carlos Correia, Rodolphe Conan, Leonardo Branco, Benoit Neichel, and Thierry Fusco
Doc ID: 324781 Received 26 Feb 2018; Accepted 09 Jun 2018; Posted 14 Jun 2018 View: PDF
Abstract: Tomographic wave-front reconstruction is the main computational bottleneck to realize real-time correctionfor turbulence-induced wave-front aberrations in future laser-assisted tomographic adaptive-optics(AO) systems for ground-based Giant Segmented Mirror Telescopes (GSMT), because of its unprecedentednumber of degrees of freedom, N, i.e. the number of measurements from wave-front sensors(WFS). In this paper, we provide an efficient implementation of the minimum-mean-square error (MMSE)tomographic wave-front reconstruction mainly useful for some classes of AO systems not requiring amulti-conjugation, such as laser-tomographic AO (LTAO), multi-objcet AO (MOAO) and ground-layerAO (GLAO) systems, but also applicable to multi-conjugate AO (MCAO) systems. This work expandsthat by R. Conan [ProcSPIE, 9148, 91480R (2014)] to the multi-wave-front, tomographic case using naturaland laser guide stars. The new implementation exploits the Toeplitz structure of covariance matrices usedin a MMSE reconstructor, which leads to an overall O(N log N) real-time complexity compared to O(N2)of the original implementation using straight vector-matrix multiplication. We show that the Toeplitzbasedalgorithm leads to 60nm rms wave-front error improvement for the European Extremely LargeTelescope Laser-Tomography AO system over a well-known sparse-based tomographic reconstruction,but the number of iterations required for suitable performance is still beyond what a real-time systemcan accommodate to keep up with the time-varying turbulence.
Symmetries of scattering factors and diffractionefficiencies in grating theory
Yasuhiko Tamura and Junichi Nakayama
Doc ID: 327057 Received 28 Mar 2018; Accepted 08 Jun 2018; Posted 14 Jun 2018 View: PDF
Abstract: This paper theoretically discusses basic topics on the reciprocity theorem and the optical theorem in thegrating theory for a plane wave reflection and transmission from a periodic rough interface betweentwo-layered homogeneous media. Based on the shadow theory, symmetries of the scattering factors anddiffraction efficiencies are newly presented in several formulas.
Petal-like zone plate: Long depth bifocaldiffractive lens and star-like beam generator
Arash Sabatyan and Marjan Golbandi
Doc ID: 326522 Received 20 Mar 2018; Accepted 06 Jun 2018; Posted 06 Jun 2018 View: PDF
Abstract: This study introduces and examines the diffraction properties of a so-calledpetal-like zone plate which comprises Fresnel zones analogous to petals. We show that focusingbehavior of this novel type of zone plate depends on the number of the petals included in theelement. For a small value of the petal frequency we observe star-like diffraction patterns at thefocal plane whose the number of the star arms equals the petal frequency of the element whenthe frequency is an odd integer and is twice as large as the petal frequency when it is an evennumber. In addition, we have shown that the star-like pattern rotates when it passes through thefocus. Moreover, it is demonstrated that the element acts as a long depth bifocal diffractive lensfor a large value of the petal frequency. The spacing between the foci is simply controlled by aso-called shifting parameter. At the same time, an annular beam is observed in the middle of theline joining the two foci together. Consequently, an axial bottle-like beam is produced around thefocus whose size could be simply monitored. Simulation results are followed and verified byexperimental works.
Photon momentum change of quasi smooth solar sails
Danilo Zola, Christian Circi, Giovanni Vulpetti, and Salvatore Scaglione
Doc ID: 324591 Received 21 Feb 2018; Accepted 06 Jun 2018; Posted 07 Jun 2018 View: PDF
Abstract: Solar photons sail (SPS) allows space missions without propellant that would otherwise not be feasible.Thrust models frequently used in the literature for the calculation of trajectories, often underestimatethe consequences that the surface roughness causes to SPS dynamics. A small variation of the thrustvector can induce a large modification of sail flight. In this work, the variation of the photon momentumvector (PMV) is computed as resulting from the incident Sun radiation taking into account the absorbedand reflected photons. The momentum resulting from diffuse light has been modeled by using vectorialscattering theories in the limit of a quasi smooth sail where the first order of Rayleigh Rice can be applied.In particular, the momentum change resulting from diffuse radiation causes a PMV reduction as well asa deviation of its direction from what foreseen in the case of a ideally smooth sail.
A partially coherent microscope imaging system in phase space
Shalin Mehta and Colin Sheppard
Doc ID: 326408 Received 20 Mar 2018; Accepted 05 Jun 2018; Posted 06 Jun 2018 View: PDF
Abstract: Explicit expressions are presented for different phase space representations (mutual intensity, Wigner distribution function, and ambiguity function) of the partially coherent image wave field in a microscope system. These are separated into system and object dependent parts. The image in phase space can be described in terms of different 6D system-dependent kernels, all Fourier transforms of the system mutual spectrum, the region of overlap of two displaced objective pupils and the effective source. The image intensity can be expressed in terms of a 4D kernel, the convolution in spatial frequency of the source and the Wigner distribution function of the objective pupil, given by a marginal of, or a section through, the respective phase space kernels.
Soleillet’s formalism of coherence and partialpolarization in 2D and 3D. Application to fluorescencepolarimetry
Oriol Arteaga and Shane Nichols
Doc ID: 328413 Received 16 Apr 2018; Accepted 04 Jun 2018; Posted 05 Jun 2018 View: PDF
Abstract: We review here the pioneering research made by Paul Soleillet on the statistical properties of light in hisdoctoral thesis from 1929. Soleillet’s wide-reaching work on polarization, coherence, fluorescence scattering,and three dimensional fields have remained largely unrecognized, yet these original contributionsrival their modern rediscoveries in both generality and form. Only now, 89 years after Soleillet’s originalpublication and stimulated by our current research on fluorescence polarimetry, we have been able tofully understand and recognize the significance of his results.
Probing spin density at the nanoscale using spin-orbitalcoupling in light scattering
Shu Gao, Chi Zhang, Xudong Cui, and Weihua Zhang
Doc ID: 327989 Received 09 Apr 2018; Accepted 03 Jun 2018; Posted 05 Jun 2018 View: PDF
Abstract: We propose a scattering-type nano-polarimeter for probing the local spin density with subwavelength spatialresolution via the spin-orbital interactions at the nanoscale. The nano-polarimeter is simple to operate, andcan be applied to a variety of asymmetric nanoprobes, allowing a direct data retrieval using two pointdetectors. Moreover, this technique is not limited to the spin-density detection and can also be used for themeasurement of any given polarization states of light, no matter whether it is free-space propagating wave ornonpropagating wave bound in the near-field region of nanostructures.
Halo and subsurface scattering in the transparentcoating on top of a diffusing material
Lionel Simonot, Mathieu Hébert, Morgane Gerardin, Cyrielle Monpeurt, and Thierry Fournel
Doc ID: 331548 Received 11 May 2018; Accepted 31 May 2018; Posted 01 Jun 2018 View: PDF
Abstract: Strongly scattering supports coated with thick transparent medium display a bright halo with characteristic ringshape when illuminated in one point by a thin pencil of light. The halo, whose size is related to the coatingthickness, is due to the Fresnel internal reflections of the light scattered by the diffusing support at the coating-airinterface. The angular distribution of the reflected light strongly varies over the halo according to the distance fromthe point initially illuminated, a fact that cannot be observed when a large area of the surface is illuminated as inusual reflectance and BRDF measurements. By considering a Lambertian background and a transparent layer ontop of it, both of them being possibly absorbing, we develop a bidirectional subsurface scattering reflectancedistribution function (BSSRDF) model, based on analytical equations and matrix numerical computation, whichenables a detailed description of the spatial and angular distribution of the scattered light including the multiplereflections between the background and the coating-air interface. Some applications in which this subsurfacescattering phenomenon can be an issue are addressed, such as the reflectance measurement which can beundervalued when the geometry is not adapted to the coating thickness, or the impact of the phenomenon onheterogeneously colored surfaces such as coated or laminated halftone prints.
Wavelet–based iterative perfect reconstruction in computational integral imaging
Xiao-Wei Li, Lei Li, and Qiong-Hua Wang
Doc ID: 308844 Received 10 Oct 2017; Accepted 29 May 2018; Posted 31 May 2018 View: PDF
Abstract: In this paper, we propose a new computational integral imaging (CII) method via the iterative perfect reconstruction technique to improve the visual quality of reconstructed 3D scenes. As is well-known, the resulting images reconstructed by CII reconstruction suffer from artifacts, which results in the degradation of visual quality. To solve this problem, the regularization and iterative back-projection (IBP) based super-resolution (SR) reconstruction algorithms have been shown to be effective for high visual quality reconstruction. However, the computation of the regularization algorithm is very expensive, and the deblurring process of the IBP algorithm makes it very sensitive to noise. To address these challenges, this paper proposes an iterative perfect reconstruction algorithm to address the low visual quality and noise issue. Experimental results indicate that this proposed method outperforms the conventional SR reconstruction-based CII methods.
An Expectation-Maximization Algorithm for Amplitude Estimation of Saturated Optical Transient Signals
Aaron Lanterman and Matthew Kagie
Doc ID: 318842 Received 03 Jan 2018; Accepted 29 May 2018; Posted 31 May 2018 View: PDF
Abstract: This paper addresses parameter estimation for an optical transient signal when the received data has been right-censored. We develop an expectation-maximization (EM) algorithm to estimate the amplitude of a Poisson intensity with a known shape in the presence of additive background counts, where the measurements are subject to saturation effects. We compare the results of our algorithm with those of an EM algorithm that is unaware of the censoring.
Polarization coherent optical communications with adaptive polarization control over atmospheric turbulence
Anhong Dang, Shengli Ding, Ruijie Li, and Yufei Luo
Doc ID: 322724 Received 07 Feb 2018; Accepted 28 May 2018; Posted 31 May 2018 View: PDF
Abstract: In wireless optical communication (WOC) systems, coherent detection scheme suffers severe performance degradation due to the phase fluctuation and polarization offset. To deal with such challenges, we proposed a polarization coherent optical communication scheme with adaptive polarization control (PCPC), where a continuous wave light transmitted is split into two paths, one is the signal light modulated by binary phase shift keying (BPSK) and the other is reference light, both of them are orthogonal with each other and combined before being sent to free space. In the receiving site, the interference between the two lights can effectively suppress the atmospheric turbulence induced phase fluctuation. Furthermore, we propose an adaptive polarization control scheme for eliminating the polarization offset caused by the transceivers misalignment and the atmospheric turbulence. Performance evaluation of PCPC scheme with analytical expressions and numerical simulations show that the PCPC scheme can effectively suppress the phase fluctuation without phase-locked loop and phase tracking algorithm, thus the PCPC scheme outperforms the traditional coherent modulation in turbulence channel. An elaborate designed indoor experiment is implemented to verify the scheme performance, where the measured residual phase fluctuation and measured residual polarization offset are both very small, and the experimental bit error rate (BER) performance can conform closely to that of the theory.
Modal-based phase retrieval using Gaussian radial basis functions
Pieter Piscaer, Abhimanyu Gupta, Oleg Soloviev, and Michel Verhaegen
Doc ID: 325986 Received 30 Mar 2018; Accepted 26 May 2018; Posted 31 May 2018 View: PDF
Abstract: In this paper, we propose the use of Gaussian radial basis functions (GRBF) to model the generalized pupil function for phase retrieval. The selection of the GRBF hyper-parameters are analysed to achieve an increased accuracy of approximation. The performance of the GRBF-based method is compared in a simulation study with another modal-based approach considering extended Nijboer-Zernike (ENZ) polynomials. The almost local character of the GRBF makes them a much more flexible basis with respect to the pupil geometry. It has been shown that for aberrations containing higher spatial frequencies, the GRBF outperform ENZ polynomials significantly even on a circular pupil. Moreover, the flexibility has been demonstrated by considering the phase retrieval problem on an annular pupil.