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Journal of the Optical Society of America A

Journal of the Optical Society of America A

| OPTICS, IMAGE SCIENCE, AND VISION

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Early Posting

Accepted papers to appear in an upcoming issue

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April


Incorporation of Polar Mellin Transform in a Hybrid Optoelectronic Correlator for Scale and Rotation Invariant Target Recognition

  • Mehjabin Sultana Monjur, Shih Tseng, Renu Tripathi, and M. Shahriar
  • received 02/12/2014; accepted 04/16/2014; posted 04/17/2014; Doc. ID 206271
  • [full text: PDF (860) KB)]
  • Abstract: In this paper, we show that our proposed hybrid optoelectronic correlator (HOC), which correlates images using spatial light modulators (SLMs), detectors and field programmable gate arrays (FPGAs), is capable of detecting objects in a scale and rotation invariant manner, along with the shift invariance feature, by incorporating polar mellin transform (PMT). For realistic images, we cut out a small circle at the center of the fourier transforom domain, as required for PMT, and illustrate how this process corresponds to correlating images with real and imaginary parts. Furthermore, we show how to carry out shift, rotation and scale invariant detection of multiple matching objects simultaneously, a process previously thought to be incompatible with PMT based correlators. We present results of numerical simulations to validate the concepts.

Keywords (OCIS):

  • (070.0070) Fourier optics and signal processing : Fourier optics and signal processing
  • (070.4550) Fourier optics and signal processing : Correlators
  • (100.0100) Image processing : Image processing
  • (100.4550) Image processing : Correlators
  • (130.0250) Integrated optics : Optoelectronics
  • (100.3005) Image processing : Image recognition devices

Improved Degree of Polarization-Based Differential Group Delay Measurements

  • Jason Pye and David Yevick
  • received 02/27/2014; accepted 04/16/2014; posted 04/17/2014; Doc. ID 206771
  • [full text: PDF (279) KB)]
  • Abstract: The time-averaged Stokes vectors obtained after polarization scrambled light containing multiple, independently polarized frequency components traverses an optical fiber collectively form a surface in Stokes space. The geometry of this surface can be directly related to the polarization mode dispersion (PMD) of the fiber. This paper examines both numerically and experimentally an improved method for performing such measurements. Additionally, it quantifies the surfaces associated with input pulses containing an arbitrary set of equally spaced frequencies.

Keywords (OCIS):

  • (060.2300) Fiber optics and optical communications : Fiber measurements
  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (060.2400) Fiber optics and optical communications : Fiber properties
  • (060.2430) Fiber optics and optical communications : Fibers, single-mode

An optical encryption and authentication scheme using asymmetric keys

  • Naveen Nishchal and Sudheesh Rajput
  • received 03/17/2014; accepted 04/15/2014; posted 04/15/2014; Doc. ID 208277
  • [full text: PDF (858) KB)]
  • Abstract: We propose a novel optical information encryption and authentication scheme that uses asymmetric keys generated by phase-truncation approach and phase-retrieval algorithm. Multiple images bonded with random phase masks are Fourier transformed and obtained spectra are amplitude- and phase-truncated. The phase-truncated spectra are encoded into single random intensity image using phase-retrieval algorithm. Unlike most of the authentication schemes, in this study, only one encrypted reference image is required for verification of multiple secured images. The conventional double random phase encoding and correlation techniques are employed for authentication verification. The computer simulation results and theoretical explanation prove the effectiveness of the proposed scheme.

Keywords (OCIS):

  • (070.0070) Fourier optics and signal processing : Fourier optics and signal processing
  • (070.4550) Fourier optics and signal processing : Correlators
  • (100.0100) Image processing : Image processing
  • (100.4998) Image processing : Pattern recognition, optical security and encryption

Jones matrices of perfectly conducting metallic polarizers

  • Philippe Boyer
  • received 03/07/2014; accepted 04/14/2014; posted 04/15/2014; Doc. ID 207754
  • [full text: PDF (2151) KB)]
  • Abstract: We deduce from Monomode Modal Method the analytical expressions of transmission and reflexion Jones matrices of an infinitely conducting metallic screen periodically pierced by subwavelength holes. The study is restricted to normal incidence and to the case of neglected evanescent fields (far-field) which covers many common cases. When only one non-degenerate mode propagates in cavities, they take identical forms to those of a polarizer, with Fabry-Perot-like spectral resonant factors depending on grating parameters. The isotropic or birefringent properties are then obtained when holes support two orthogonal polarization modes. This basic formalism is finally applied to design compact and efficient metallic half-wave plates.

Keywords (OCIS):

  • (050.1950) Diffraction and gratings : Diffraction gratings
  • (160.0160) Materials : Materials
  • (230.5440) Optical devices : Polarization-selective devices
  • (260.5430) Physical optics : Polarization
  • (050.6624) Diffraction and gratings : Subwavelength structures

Rotation of the polarization direction and reversal of helicity of ultrashort pulsed beams propagating in free space

  • Balazs Major, Miguel Porras, and Zoltan Horvath
  • received 02/05/2014; accepted 04/09/2014; posted 04/15/2014; Doc. ID 206034
  • [full text: PDF (374) KB)]
  • Abstract: We unveil the origin of the recently revealed polarization state changes of polarization-shaped few-cycle pulses induced by free space beam propagation. Simple rules are formulated to show how the orientation and ellipticity of the instantaneous polarization ellipse of the source and propagated pulses relate to each other. We demonstrate our findings with examples that clearly display the relationships found and highlight the their relevance. We show, for example, that pulses often used in high-harmonic or attosecond pulse generation rotate as a whole during free beam propagation or upon focusing, or that other pulses may reverse their ellipticity from right-handed to left-handed, these effect being independent of the beam size and/or focal length. We also present how these instantaneous polarization state changes could be noticed in classical measurements of light polarization using polarizers, phase retarders and time-integrating detectors.

Keywords (OCIS):

  • (030.1670) Coherence and statistical optics : Coherent optical effects
  • (260.5430) Physical optics : Polarization
  • (320.2250) Ultrafast optics : Femtosecond phenomena

Quantitative confocal spiral phase contrast

  • Marc Guillon and Marcel Lauterbach
  • received 02/25/2014; accepted 04/08/2014; posted 04/09/2014; Doc. ID 207112
  • [full text: PDF (1215) KB)]
  • Abstract: We demonstrate quantitative phase delay measurement with a Spiral Phase Contrast microscope working in confocal mode. Such a confocal configuration is sensitive to weak phase objects due to background rejection, but does not give direct access to the phase delay introduced by the sample. We develop a theory showing that shifting the illumination spot relatively to the detector gives access to the local phase gradient in first order approximation. Subsequently, we present an iterative integration algorithm for phase delay measurements. This approach is validated on simulated and experimental calibrated images. Finally the algorithm is applied to measure the phase profile of a cell, in which phase delays of 10mrad are observed.

Keywords (OCIS):

  • (070.6110) Fourier optics and signal processing : Spatial filtering
  • (180.1790) Microscopy : Confocal microscopy
  • (180.3170) Microscopy : Interference microscopy

Tight focusing of a double-ring-shaped, azimuthally polarized beam through a dielectric interface

  • Jianhua Shu, Ziyang Chen, Jixiong Pu, and Yongxin Liu
  • received 02/28/2014; accepted 04/08/2014; posted 04/09/2014; Doc. ID 207386
  • [full text: PDF (2098) KB)]
  • Abstract: We investigate the tight focusing properties of a double-ring-shaped, azimuthally polarized vector beam (DRS-APVB) by use of vectorial Debye theory. It is shown that a dark channel with an ultra-long depth of focus (~106) and subwavelength focal holes (~0.5) can be generated by focusing a DRS-APVB through a dielectric interface with an annular high numerical aperturte (NA) objective lens. The influence of the NA of the objective, the relative refractive index of two media, and the probe depth of the system on the focusing properties of the dark channel has been studied in detail. Such a nondiffracting dark channel could find potential applications in atom optical experiments, such as with atomic lenses, atom traps, and atom switches.

Keywords (OCIS):

  • (030.1640) Coherence and statistical optics : Coherence
  • (260.0260) Physical optics : Physical optics
  • (260.5430) Physical optics : Polarization

On Performance of Select Color-Difference Formulas in the Blue Region

  • R. Shamey, R. Cao, T. Tomasino, S. Zaidy, K. Iqbal, Juan Lin, and S. Lee
  • received 12/23/2013; accepted 04/08/2014; posted 04/15/2014; Doc. ID 203595
  • [full text: PDF (1758) KB)]
  • Abstract: The main objective of this work was to test the performance of major formulas for assessment of small suprathreshold color differences in the blue region. The models examined include CIELAB based equations including CIELAB, CIE94, CIEDE2000, CMC (l:c), BFD (l:c); and formulas based on more uniform color spaces such as DIN99d, CAM02-SCD, CAM02-UCS, OSA-GP and OSA-Eu in comparison against data obtained via visual assessments. For this purpose a dataset around the CIE high chroma blue color center, hereafter called NCSU-B2, was developed. The NCSU-B2 dataset is comprised of 65 textile substrates, and a standard, with a mean ΔE*ab color difference of 2.72 ranging from 0.54-5.72. Samples were visually assessed by 26 subjects against the reference gray scale in three separate trials with at least 24 hours between assessments and a total of 5070 assessments were obtained. Standardized Residual Sum of Squares (STRESS) index was used to examine the performance of various formulas for this dataset, as well as a previously developed NCSU-B1 low chroma blue dataset [Color Res. Appl. 36(1), 27-41, 2011], and blue centers from other established visual datasets. Results show that formulas based on more recent uniform color spaces provide better agreement with perceptual data compared to models based on CIELAB space.

Keywords (OCIS):

  • (330.1690) Vision, color, and visual optics : Color
  • (330.1730) Vision, color, and visual optics : Colorimetry

Fast non-paraxial scalar focal fifield calculations

  • Matthias Hillenbrand, Armin Hoffmann, Damien Kelly, and Stefan Sinzinger
  • received 02/18/2014; accepted 04/07/2014; posted 04/15/2014; Doc. ID 206637
  • [full text: PDF (2124) KB)]
  • Abstract: An efficient algorithm for calculating non-paraxial scalar field distributions in the focal region of a lens is discussed. The algorithm is based on Fast Fourier Transform implementations of the first Rayleigh-Sommerfeld diffraction integral and assumes that the input field at the pupil plane has a larger extent than the field in the focal region. A sampling grid is defined over a finite region in the output plane, and referred to as a tile. The input field is divided into multiple separate spatial regions of the size of the output tile. Finally, the input tiles are added coherently to form a summed tile which is propagated to the output plane. Since only a single tile is propagated there are significant reductions of computational load and memory requirements. We combine this technique with a numerical method for increasing the number of samples in the output plane while keeping the output extent constant. Properties and limitations of the algorithms are discussed. An example of the combined method with a 790x speedup, a reduction of the memory requirements by more than 99.9% and a relative error below 0.1% is presented.

Keywords (OCIS):

  • (050.1960) Diffraction and gratings : Diffraction theory
  • (110.2990) Imaging systems : Image formation theory
  • (220.2560) Optical design and fabrication : Propagating methods

The role of hybrid wave in electromagnetic enhancement by a metallic groove doublet

  • Siwen Zhang, Haitao Liu, and Xiaodong Sun
  • received 01/21/2014; accepted 04/07/2014; posted 04/09/2014; Doc. ID 205000
  • [full text: PDF (393) KB)]
  • Abstract: We provide elaborate investigations about the role of hybrid wave in electromagnetic enhancement by a groove doublet in metallic substrate. A simple hybrid wave model method is employed to explore the detailed effect of hybrid wave on electromagnetic enhancement. The obtained data show that the reflection of HW by the nearby nano-groove is so weak (<0.1) that can be neglected. Giant electromagnetic enhancement can be achieved by choosing the groove doublet parameters properly to strengthen the attribution of the propagation of HW. Our analysis also reveals a compensation of low electromagnetic enhancement for wide groove attributing to the excitation of HW. The dependence of HW and electromagnetic enhancement on the noble metal type is also discussed.

Keywords (OCIS):

  • (240.6690) Optics at surfaces : Surface waves
  • (260.3910) Physical optics : Metal optics
  • (050.6624) Diffraction and gratings : Subwavelength structures
  • (240.6695) Optics at surfaces : Surface-enhanced Raman scattering

Recovering Euclidean Structure from Principal-Axes Paralleled Conics: Applications to Camera Calibration

  • Zijian Zhao and Ying Weng
  • received 01/13/2014; accepted 04/05/2014; posted 04/15/2014; Doc. ID 204565
  • [full text: PDF (617) KB)]
  • Abstract: We focus on recovering the 2D Euclidean structure further for camera calibration from the projections of N parallel similar conics in this paper. This work denotes that the conic dual to the absolute points (CDAP) is the general form of the conic dual to the circular points (CDCP), so it encodes the 2D Euclidean structure. However, the geometric size of the conic should be known, if we utilize the CDAP. Under some special conditions (concentric conics), we proposed the rank-1,2 constraints. Our work relaxes the problem conditions and gives a more general framework than before. Experiments with simulated and real data are carried out to show the validity of the proposed algorithm.

Keywords (OCIS):

  • (150.0150) Machine vision : Machine vision
  • (330.7310) Vision, color, and visual optics : Vision
  • (150.1135) Machine vision : Algorithms
  • (150.1488) Machine vision : Calibration

Avalanche and bit independence characteristics of double random phase encoding in the Fourier and Fresnel domains

  • Inkyu Moon, Faliu Yi, Yeon H. Lee, and Bahram Javidi
  • received 01/10/2014; accepted 04/03/2014; posted 04/03/2014; Doc. ID 204434
  • [full text: PDF (575) KB)]
  • Abstract: In this paper, we evaluate the avalanche effect and bit independence properties of the double random phase encoding (DRPE) algorithm in the Fourier and Fresnel domains. Experimental results show that DRPE has excellent bit independence characteristics in both the Fourier and Fresnel domains. However, DRPE achieves better avalanche effect results in the Fresnel domain than in the Fourier domain. DRPE gives especially poor avalanche effect results in the Fourier domain when only one bit is changed in the plaintext or in the encryption key. Despite this, DRPE shows satisfactory avalanche effect results in the Fresnel domain when any other number of bits changes in the plaintext or in the encryption key. To the best of our knowledge, this is the first report on the avalanche effect and bit independence behaviors of optical encryption approaches for bit units.

Keywords (OCIS):

  • (200.3050) Optics in computing : Information processing
  • (060.4785) Fiber optics and optical communications : Optical security and encryption
  • (100.4998) Image processing : Pattern recognition, optical security and encryption

Numerical Stability issues on Channelized Hotelling Observer under different background assumptions

  • Di Ge, Lu Zhang, Christine Cavaro-Ménard, and Patrick Le Callet
  • received 11/19/2013; accepted 04/02/2014; posted 04/07/2014; Doc. ID 201628
  • [full text: PDF (437) KB)]
  • Abstract: This paper addresses the numerical stability issue on the Channelized Hotelling Observer (CHO). The CHO is a well-known approach in the medical image quality assessment domain. Many researchers have found that the detection performance of the CHO does not increase with the number of channels, contrary to expectation. And to our knowledge, the reason of this phenomenon has not been addressed thoroughly. We illustrate in the present study that this is due to the ill-conditioning of the scatter matrix : its direct inverse in the current CHO methods can yield unstable numerical behaviors even in a very favorable setting using rotationally symmetric backgrounds and the adapted L-G channels. We propose a solution based on Tikhonov regularization and show in this paper the stabilized detection performances with increasing channels and improvements in the asymptotic value. This work is preliminary to the application of CHO (and other channelized model observers) both in terms of parameter adjustment and channel optimization with respect to human observation specificities.

Keywords (OCIS):

  • (000.4430) General : Numerical approximation and analysis
  • (110.2960) Imaging systems : Image analysis
  • (110.2970) Imaging systems : Image detection systems
  • (110.3000) Imaging systems : Image quality assessment
  • (110.3200) Imaging systems : Inverse scattering

Explaining the success of Kogelnik’s coupled-wave theory by means of perturbation analysis

  • Heinz-Juergen Schmidt, Mirco Imlau, and Kay-Michael Voit
  • received 12/17/2013; accepted 04/01/2014; posted 04/01/2014; Doc. ID 203083
  • [full text: PDF (532) KB)]
  • Abstract: The problem of diffraction of an electromagnetic wave by a thick hologram grating can be solved by the famous Kogelnik’s coupled-wave theory (CWT) to a very high degree of accuracy. We confirm this finding by comparing the CWT and the exact result for a typical example and propose an explanation in terms of perturbation theory. To this end we formulate the problem of diffraction as a matrix problem following similar well-known approaches, especially the rigorous coupled wave theory (RCWT). We allow for a complex permittivity modulation and a possible phase-shift between refractive index and absorption grating and explicitly incorporate appropriate boundary conditions. The problem is solved numerically exact for the specific case of a planar un-slanted grating and a set of realistic values of the material’s parameters and experimental conditions. Analogously, the same problem is solved for a two-dimensional truncation of the underlying matrix that would correspond to a CWT approximation but without the usual further approximations. We verify a close coincidence of both results even in the off-Bragg region and explain this result by means of a perturbation analysis of the underlying matrix problem. Moreover, the coupled-wave theory is found not only to coincide with the perturbational approximation in the in-Bragg and the extreme off-Bragg case, but also to interpolate between these extremal regimes.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (060.2420) Fiber optics and optical communications : Fibers, polarization-maintaining
  • (140.3490) Lasers and laser optics : Lasers, distributed-feedback
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

March


An annular focusing lens based on transformation optics

  • Bai Bing Xu, Wei Xiang Jiang, Guan Xia Yu, and Tie Jun Cui
  • received 01/06/2014; accepted 03/31/2014; posted 04/01/2014; Doc. ID 204143
  • [full text: PDF (7989) KB)]
  • Abstract: We propose and design a kind of annular focusing lens based on the transformation optics. Based on the method of eigen-mode expansions, closed-form expressions are derived to analyze the proposed annular lens rigorously. We show that the annular lens has excellent focusing property. Even when a barrier (such as a conducting cylinder) exists in the center of the lens, the analytical results demonstrate that the waves are still guided to propagate smoothly and focused on a spot.

Keywords (OCIS):

  • (080.2710) Geometric optics : Inhomogeneous optical media
  • (160.1190) Materials : Anisotropic optical materials
  • (220.3630) Optical design and fabrication : Lenses
  • (160.3918) Materials : Metamaterials

Design of optical system for collimating the light of LED uniformly

  • Chen Chen and Xiaohui Zhang
  • received 12/19/2013; accepted 03/31/2014; posted 04/02/2014; Doc. ID 203457
  • [full text: PDF (2669) KB)]
  • Abstract: A type of optical system consisting of one total internal reflection (TIR) lens and two reflectors is designed for collimating the light of LED to a uniform pattern. Application of this kind of optical includes underwater light communication and underwater image system. The TIR lens collimates all the light of LED to a non-uniform plane wave-front. The double reflector system redistributes the plane wave-front uniformly and collimates again. Three optical systems produced different radius of output light pattern are designed. The result shows that the uniformity of the designed optical is lager than 0.76 and total output efficiency (TOE) is lager than 89%. At the same time we conclude that the radius of the output reflector should not smaller than the input reflector in order to keep high uniformity and TOE.

Keywords (OCIS):

  • (080.2740) Geometric optics : Geometric optical design
  • (220.2945) Optical design and fabrication : Illumination design
  • (080.4035) Geometric optics : Mirror system design
  • (080.4295) Geometric optics : Nonimaging optical systems

Numerical solutions of the Rayleigh equations for the scattering of light from a two-dimensional randomly rough perfectly conducting surface

  • T. Nordam, P. A. Letnes, I. Simonsen, and A. Maradudin
  • received 01/28/2014; accepted 03/31/2014; posted 04/02/2014; Doc. ID 203736
  • [full text: PDF (1783) KB)]
  • Abstract: We present rigorous, nonperturbative, purely numerical solutions of the Rayleigh equations for the scattering of p- and s-polarized light from a two-dimensional randomly rough perfectly conducting surface. The solutions are used to calculate the reflectivity of the surface, the mean differential reflection coefficients, and the full angular distribution of the intensity of the scattered field. These results are compared with the results of our earlier rigorous numerical solutions of the Stratton-Chu equations [Phys. Rev. A 82, 013806(1-13) (2010)], and very good agreement is found.

Keywords (OCIS):

  • (240.0240) Optics at surfaces : Optics at surfaces
  • (240.5770) Optics at surfaces : Roughness
  • (240.6680) Optics at surfaces : Surface plasmons
  • (290.5880) Scattering : Scattering, rough surfaces

Electromagnetic Subsurface Prospecting by a Multi-Focusing Inexact Newton Method within the Second-Order Born Approximation

  • Marco Salucci, Giacomo Oliveri, Andrea Randazzo, Matteo Pastorino, and Andrea Massa
  • received 01/29/2014; accepted 03/20/2014; posted 04/03/2014; Doc. ID 205700
  • [full text: PDF (459) KB)]
  • Abstract: In this paper the reconstruction of shallow buried object is addressed by an electromagnetic inverse scattering method based on combining different imaging modalities. In particular, the proposed approach integrates the inexact-Newton method with an iterative multi-scaling approach. Moreover, the use of the second-order Born approximation is exploited. A numerical validation is provided concerning the potentialities arising by combining the regularization capabilities of the inexact-Newton method and the effectiveness of the multifocusing strategy to mitigate the non-linearity and ill-posedness of the inversion problem. Comparisons with the standard "bare" approach in terms of accuracy, robustness, noise levels, and computational efficiency are also included.

Keywords (OCIS):

  • (110.0110) Imaging systems : Imaging systems
  • (280.0280) Remote sensing and sensors : Remote sensing and sensors
  • (290.3200) Scattering : Inverse scattering
  • (110.1758) Imaging systems : Computational imaging
  • (110.6955) Imaging systems : Tomographic imaging
  • (110.3010) Imaging systems : Image reconstruction techniques

(30th Anniversary) Dictionaries for Image and Video-based Face Recognition (mini-review)

  • Vishal Patel, Yi-Chen Chen, Rama Chellappa, and P. Jonathon Phillips
  • received 01/06/2014; accepted 03/18/2014; posted 03/26/2014; Doc. ID 203939
  • [full text: PDF (1678) KB)]
  • Abstract: In recent years, sparse representation and dictionary learning-based methods have emerged as powerful tools for efficiently processing data in non-traditional ways. A particular area of promise for these theories is face recognition. In this paper, we review the role of sparse representation and dictionary learning for efficient face identification and verification. Recent face recognition algorithms from still images and videos are reviewed. In particular, discriminative dictionary learning algorithms as well as methods based on weakly supervised learning and domain adaptation are summarized. Some of the compelling challenges and issues that confront research in face recognition using sparse representations and dictionary learning are also outlined.

Keywords (OCIS):

  • (100.0100) Image processing : Image processing
  • (100.5010) Image processing : Pattern recognition
  • (150.1135) Machine vision : Algorithms

Classical Light Beams and Geometric Phases

  • N. Mukunda, S. Chaturvedi, and R. Simon
  • received 12/17/2013; accepted 03/12/2014; posted 03/14/2014; Doc. ID 203029
  • [full text: PDF (496) KB)]
  • Abstract: We present a study of geometric phases in classical wave and polarisation optics using the basic mathematical framework of quantum mechanics. Important physical situations taken from scalar wave optics, pure polarisation optics, and the behaviour of polarisation in the eikonal or ray limit of Maxwell's equations in a transparent medium are considered. The case of a beam of light whose propagation direction and polarisation state are both subject to change is dealt with, attention being paid to the validity of Maxwell's equations at all stages. Global topological aspects of the space of all propagation directions are discussed using elementary group theoretical ideas, and the effects on geometric phases are elucidated.

Keywords (OCIS):

  • (030.1640) Coherence and statistical optics : Coherence
  • (260.5430) Physical optics : Polarization
  • (350.5500) Other areas of optics : Propagation

Articles 1 to 20 of 21 Next Page >>





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