OSA's Digital Library

Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  •  

Optics InfoBase > Applied Optics > Early Posting

Early Posting

Accepted papers to appear in an upcoming issue

OSA now posts prepublication articles as soon as they are accepted and cleared for production. See the FAQ for additional information.

Articles 1 to 20 of 100 Next Page >>

October


(LC2014) The 35 minute green flash observed at Little America on 16 Oct 1929: A retrospective study

  • James Lock
  • received 08/08/2014; accepted 10/20/2014; posted 10/21/2014; Doc. ID 220624
  • [full text: PDF (417) KB)]
  • Abstract: On 16 Oct 1929 five members of the Byrd Expedition I observed an intermittent 35 min green flash at the Little America station (latitude -78.57o) in Antarctica. The flash was the result of strong atmospheric refraction, likely associated with a subcritical Novaya Zemlya mirage. This paper examines the constraints placed on the observation by the earth-sun orbital kinematics. It is found that the length of the observation cannot be explained solely by the slowness of the setting rate of the sun, nor the time required just before the beginning of the Antarctic summer for the top of the sun to set, reach its relative minimum position at the horizon, and then rise again. The observed length of the effect, however, is consistent with the sun effectively setting and rising twice during the observation, with the first effective rising being the result of the observers climbing up the radio towers at the Little America station in order to keep the top of the sun in view.

Keywords (OCIS):

  • (010.0010) Atmospheric and oceanic optics : Atmospheric and oceanic optics
  • (010.1290) Atmospheric and oceanic optics : Atmospheric optics
  • (010.1300) Atmospheric and oceanic optics : Atmospheric propagation

Truncated corner-cubes with near-perfect retroreflection efficiency

  • Eunkyong Moon, Shin-Woong Park, Hayun Chung, Joon-Yong Lee, Chanyeol Bae, Jin-Woo Kim, and Hwi Kim
  • received 07/03/2014; accepted 10/19/2014; posted 10/21/2014; Doc. ID 216323
  • [full text: PDF (2780) KB)]
  • Abstract: By isolating a finite effective volume from a conventional triangular pyramid corner-cube, we obtain truncated corner-cube structures with greatly enhanced retroreflection efficiency. We explore an optimal truncated corner-cube with near 100% retroreflection efficiency based on the expectation that the traveling paths of the optical rays can be localized in the finite effective volume of the structure and, as a result, truncated corner-cubes with perfect efficiency can be produced.

Keywords (OCIS):

  • (080.2740) Geometric optics : Geometric optical design
  • (120.4570) Instrumentation, measurement, and metrology : Optical design of instruments
  • (120.5700) Instrumentation, measurement, and metrology : Reflection

Characterizing integration time and gray level related non-linearities in a NMOS sensor

  • Javier Pacheco-Labrador, Alejandro Ferrero, and M. Pilar Martín
  • received 07/24/2014; accepted 10/19/2014; posted 10/21/2014; Doc. ID 217517
  • [full text: PDF (583) KB)]
  • Abstract: We report a non-linearity effect related to the integration time in a double-beam spectroradiometer equipped with two NMOS sensors. This effect can be explained by the addition of photoelectrons produced by the radiant flux on the sensors during the readout phase to the photoelectrons produced during the measurement phase. A new method is proposed to characterize and correct both gray-level and integration-time-related non-linearities (GLITNL) in NMOS sensors. This method is experimentally simple and outperforms other commonly used correction procedures.

Keywords (OCIS):

  • (040.5160) Detectors : Photodetectors
  • (120.0280) Instrumentation, measurement, and metrology : Remote sensing and sensors
  • (120.5630) Instrumentation, measurement, and metrology : Radiometry

The Localization of Light in The Atomic Medium Induced By The Hermite-Cosine-Gauss Field

  • Xing Wei, Bin Chen, Chunfang Wang, and Jing Cheng
  • received 08/04/2014; accepted 10/19/2014; posted 10/21/2014; Doc. ID 219883
  • [full text: PDF (755) KB)]
  • Abstract: This paper provides a way of realizing light wave localization via electromagnetically induced transparency, which is quite different from the traditional, off-resonant mechanism-based Aubry-Andre model. The localization of light in one-dimensional atomic medium is reported here. The medium suggested in this paper is a resonant cold atomic ensemble with N-configuration, which can be modulated to be a quasi-periodic structure in the center area. As the paraxial signal field propagates in the medium, localization can be realized. The localization point and the propagation properties of the signal field are studied in this paper.

Keywords (OCIS):

  • (190.0190) Nonlinear optics : Nonlinear optics
  • (270.0270) Quantum optics : Quantum optics
  • (270.1670) Quantum optics : Coherent optical effects

Sellmeier and thermo-optic dispersion formulas for LiInS2

  • Kiyoshi Kato and Nobuhiro Umemura
  • received 08/04/2014; accepted 10/19/2014; posted 10/21/2014; Doc. ID 220388
  • [full text: PDF (494) KB)]
  • Abstract: This paper reports on the improved Sellmeier and thermo-optic dispersion formulas for LiInS2, which provide an excellent reproduction of the temperature-dependent phase-matching conditions for second, sum-, and difference-frequency generation (SHG, SFG, and DFG) achieved in the 1.0642-10.5910μm range.

Keywords (OCIS):

  • (160.4330) Materials : Nonlinear optical materials
  • (190.2620) Nonlinear optics : Harmonic generation and mixing
  • (190.4400) Nonlinear optics : Nonlinear optics, materials

Design of an ultra-short coupler in an asymmetric twin-waveguide structure using transformation optics

  • Kaisheng Chen, Zhuyang Huang, Gaoneng Dong, and Xinliang Zhang
  • received 07/28/2014; accepted 10/17/2014; posted 10/21/2014; Doc. ID 219931
  • [full text: PDF (1194) KB)]
  • Abstract: An integrated vertical coupler that transfers light from the lower passive waveguide to the upper active waveguide in an asymmetric twin-waveguide integration structure in InGaAsP/InP material system is designed using transformation optics. The length of the coupler is as short as 3 μm, which is two orders of magnitude shorter than that of traditional tapered couplers. According to three-dimensional full-wave simulations, the designed optimized coupler characterizes a high coupling efficiency of 94.9% and a low reflection at the wavelength of 1.55 μm. Subsequently, quasi-conformal mapping is employed to reduce the material complexity and make it possible to realize the coupler by purely using isotropic dielectric material. Applying transformation optics to integrated photonic devices may motivate new applications and improve the integration density on the InP platform.

Keywords (OCIS):

  • (130.3120) Integrated optics : Integrated optics devices
  • (160.3918) Materials : Metamaterials

Fabrication of UV-curable adhesive bottle-like micro-resonators by wetting and photocuring

  • Guoqiang Gu, Changlei Guo, Zhiping Cai, Huiying Xu, Lujian Chen, Hongyan Fu, Kaijun Che, Minghui Hong, Shufeng Sun, and Fengping Li
  • received 08/28/2014; accepted 10/17/2014; posted 10/21/2014; Doc. ID 221959
  • [full text: PDF (1528) KB)]
  • Abstract: This paper presents a remarkably simple method for the fabrication of ultraviolet (UV)-curable adhesive bottle-like micro-resonators (BLMRs). The main fabrication process involves two steps: (1) creating liquid bottle-like microcavities along the taper waist of an optical fiber taper under interfacial tension and (2) curing into solid by UV light irradiation. The shape of the BLMRs can be fitted with a truncated harmonic-oscillator profile. Whispering gallery mode (WGM) resonances of the bottle-like microcavity were excited via a tapered fiber at different positions along its axis. A cleaner spectrum with identifiable and traceable features over a broad wavelength range at the center excitation position and the estimated Q-factors close to 105 around 1.55 μm are observed. The shifts of resonance frequency by the input light power change demonstrate the potential applications of thermo-optic sensing and frequency tuning.

Keywords (OCIS):

  • (140.4780) Lasers and laser optics : Optical resonators
  • (220.4000) Optical design and fabrication : Microstructure fabrication
  • (140.3948) Lasers and laser optics : Microcavity devices

(LC2014) Infrared moon imaging for remote sensing of atmospheric smoke layers

  • Joseph Shaw, Paul Nugent, and Michael Vollmer
  • received 07/14/2014; accepted 10/16/2014; posted 10/20/2014; Doc. ID 216819
  • [full text: PDF (2129) KB)]
  • Abstract: Simultaneous visible and long-wave infrared images of the Moon were used with a simple energy-balance model to study the spatial pattern of lunar surface temperatures. The thermal images were obtained with a radiometrically calibrated, compact, low-cost, commercial infrared camera mounted on a compact telescope. Differences between the predicted and measured maximum Moon temperatures were used to determine the infrared optical depth (OD) that represents the path-integrated extinction of an elevated layer of wildfire smoke in the atmosphere. The OD values retrieved from the IR Moon images were combined with simultaneous OD measurements from a ground-based, zenith-pointing lidar operating at a wavelength of 532 nm to determine an infrared-to-visible optical depth ratio of 0.50 ± 0.18 for moderately aged wildfire smoke aerosol.

Keywords (OCIS):

  • (010.1100) Atmospheric and oceanic optics : Aerosol detection
  • (010.1290) Atmospheric and oceanic optics : Atmospheric optics
  • (010.1310) Atmospheric and oceanic optics : Atmospheric scattering
  • (010.5630) Atmospheric and oceanic optics : Radiometry
  • (010.0280) Atmospheric and oceanic optics : Remote sensing and sensors

Rocking filter induced mechanically in a highly birefringent microstructured polymer fiber

  • Gabriela Statkiewicz-Barabach, Pawel Mergo, and Waclaw Urbanczyk
  • received 07/30/2014; accepted 10/16/2014; posted 10/20/2014; Doc. ID 220103
  • [full text: PDF (2145) KB)]
  • Abstract: We present a possibility of mechanical inducement of a rocking filter in a birefringent microstructured polymer fiber, which resonantly couples polarization modes. A birefringence in the fiber used for the rocking filter fabrication is induced by two large holes adjacent to the core. Because of small pitch distance of the microstructured cladding, the phase and the group modal birefringence in this fiber are relatively high and equal respectively 1.2×10−4 and -2×10−4 at λ=800 nm, while the fiber loss is 5 dB/m at λ=850 nm. We demonstrate transmission characteristics of rocking filters mechanically induced in this fiber. A 22 dB deep first order resonance located in a visible spectral range was observed, accompanied by a second order resonance in a near infrared. We also show that by changing the filter period and load applied to the fiber, one can tune the resonance position and depth.

Keywords (OCIS):

  • (050.2770) Diffraction and gratings : Gratings
  • (160.5470) Materials : Polymers
  • (260.1440) Physical optics : Birefringence
  • (060.4005) Fiber optics and optical communications : Microstructured fibers

High Resolution Reconstruction for Terahertz Imaging

  • Li-Min Xu, Wen-Hui Fan, and Jia Liu
  • received 05/26/2014; accepted 10/15/2014; posted 10/16/2014; Doc. ID 212774
  • [full text: PDF (1525) KB)]
  • Abstract: We present high resolution reconstruction model and algorithms for terahertz imaging, taking advantage of super-resolution methodology and algorithms. The algorithms used include projection onto convex sets approach, iterative back-projection approach, Lucy-Richardson iteration, two dimensional wavelet decomposition-reconstruction. Using the first two high resolution reconstruction methods, we successfully obtain high-resolution terahertz images with improved definition and lower noise from 4 low-resolution 22×24 terahertz images taken from our home-made THz-TDS system at the same experimental conditions with 1.0 mm-pixel. Using the last two high resolution reconstruction methods, we transform one relatively low resolution terahertz image to a high-resolution terahertz image with decreased noise. This indicates great potential application of high resolution reconstruction methods in terahertz imaging with both pulsed and continuous wave terahertz sources.

Keywords (OCIS):

  • (100.2960) Image processing : Image analysis
  • (100.3020) Image processing : Image reconstruction-restoration
  • (110.6795) Imaging systems : Terahertz imaging

Determination of Point spread function of paper substrate based on light scattering simulation

  • D. Modric, K. Petric Maretic, and Aleš Hladnik
  • received 06/17/2014; accepted 10/15/2014; posted 10/16/2014; Doc. ID 214148
  • [full text: PDF (1218) KB)]
  • Abstract: The objective of this work was to establish the relationship between the calculated subsurface scattered photon distribution and the mathematical quantity known as point spread function (PSF). Photon distribution of subsurface scattered light was calculated using Monte Carlo method developed for describing reflectance and opacity of paper and of images printed on paper. The obtained normalized photon distribution made it possible to separate optical and mechanical components of dot gain for the paper-ink system. In the presented method of obtaining the reflectance profile of a screen element the PSF convolves with a modelled reflectance profile of that element. It was found that the PSF can be better approximated by means of Lorentzian function when compared to the Gaussian profile that was used in the past research on this topic.

Keywords (OCIS):

  • (100.2810) Image processing : Halftone image reproduction
  • (110.4850) Imaging systems : Optical transfer functions
  • (290.4210) Scattering : Multiple scattering
  • (110.0113) Imaging systems : Imaging through turbid media
  • (110.1758) Imaging systems : Computational imaging
  • (080.5692) Geometric optics : Ray trajectories in inhomogeneous media

Separation of Specular and Diffuse Component Using Tensor Voting in Natural Color Images

  • GueeSang Lee, Tam Nguyen, Nhat Vo, SooHyung Kim, and HyungJeong Yang
  • received 07/02/2014; accepted 10/15/2014; posted 10/16/2014; Doc. ID 215137
  • [full text: PDF (1969) KB)]
  • Abstract: Most methods for the detection and removal of specular reflections suffer from non-uniform highlight regions and/or non-converged artifacts induced by discontinuities in the surface colors, especially when dealing with highly textured, multicolored images. In this paper, a novel non-iterative and predefined constraint-free method based on tensor voting is proposed to detect and remove the highlight components of a single color image. The distribution of diffuse and specular pixels in the original image is determined using tensors’ saliency analysis, instead of comparing color information among neighbor pixels. The achieved diffuse reflectance distribution is used to remove specularity components. The proposed method is evaluated quantitatively and qualitatively over a dataset of highly textured, multicolor images. The experimental results show that our result outperforms other state-of-the-art techniques.

Keywords (OCIS):

  • (100.0100) Image processing : Image processing
  • (120.5700) Instrumentation, measurement, and metrology : Reflection
  • (150.1135) Machine vision : Algorithms
  • (010.1690) Atmospheric and oceanic optics : Color

Quality control of leather by terahertz time domain spectroscopy

  • A. Hernandez-Serrano, S. C. Corzo-Garcia, E. Garcia-Sanchez, M. Alfaro, and E. Castro-Camus
  • received 08/20/2014; accepted 10/15/2014; posted 10/16/2014; Doc. ID 221351
  • [full text: PDF (256) KB)]
  • Abstract: We use terahertz time-domain spectroscopy combined with effective-medium theory to measure moisture content and thickness of leather simultaneously. These results demonstrate that this method could become a standard quality control test for the industrial tanning process.

Keywords (OCIS):

  • (160.4890) Materials : Organic materials
  • (160.1435) Materials : Biomaterials
  • (300.6495) Spectroscopy : Spectroscopy, teraherz

Numerical investigation on the generation of high-order Laguerre-Gaussian beams in endpumped solid state lasers by introducing loss control

  • Ajian Hu, Jian Lei, Peifeng Chen, Ying Wang, and Shumo Li
  • received 09/04/2014; accepted 10/15/2014; posted 10/16/2014; Doc. ID 222245
  • [full text: PDF (1270) KB)]
  • Abstract: This paper reports a robust and systematic approach to generate high-order scalar Laguerre-Gaussian ( p,l LG ) beams in end-pumped solid-state lasers by introducing loss control. Based on the spatial distributions of Laguerre- Gaussian modes and the theory of transverse mode selection, the “loss control” is implemented by an amplitude mask in the resonator. This proposed mechanism can be divided into three categories: radial loss, azimuthal loss and the combination of radial and azimuthal loss, which correspond to excite radial high-order modes ( p,0 LG ), azimuthal high-order modes ( 0,l LG ) and regular high-order modes ( p,l LG ), respectively. By controlling the locations and thicknesses of opaque rings and lines on the mask, all kinds of p,l LG modes can be obtained. With the application of mode purity, all the generated modes possess high mode purities are greater than 93% in simulation.

Keywords (OCIS):

  • (000.4430) General : Numerical approximation and analysis
  • (140.3480) Lasers and laser optics : Lasers, diode-pumped
  • (140.4780) Lasers and laser optics : Optical resonators
  • (140.3295) Lasers and laser optics : Laser beam characterization

(DH3D2014) Real-time, fast-speed and high-accuracy 3D imaging and shape measurement

  • Hieu Nguyen, Hien Kieu, Zhaoyang Wang, and Minh Le
  • received 09/02/2014; accepted 10/15/2014; posted 10/16/2014; Doc. ID 222354
  • [full text: PDF (1976) KB)]
  • Abstract: In spite of the recent advances in 3D shape measurement and geometry reconstruction, simultaneously achieving fast speed and high accuracy performance remains a big challenge in practice. In this paper, a 3D imaging and shape measurement system is presented to tackle such a challenge. The fringe-projection-profilometry-based system employs a number of advanced approaches, such as composition of phase-shifted fringe patterns, externally triggered synchronization of system components, a generalized system setup, an ultra-fast phase-unwrapping algorithm, a flexible system calibration method, a robust gamma correction scheme, multi-thread computation and processing, graphics-processing-unit-based image display, and so on. Experiments have shown that the proposed system can acquire and display high-quality 3D reconstructed images or video stream at a speed of 45 frames per second with relative accuracy of 0.04% or at a reduced speed of 22.5 frames per second with enhanced accuracy of 0.01%. The 3D imaging and shape measurement system shows great promise of satisfying the ever-increasing requirements in scientific and engineering applications.

Keywords (OCIS):

  • (110.6880) Imaging systems : Three-dimensional image acquisition
  • (120.2650) Instrumentation, measurement, and metrology : Fringe analysis
  • (120.6660) Instrumentation, measurement, and metrology : Surface measurements, roughness
  • (150.6910) Machine vision : Three-dimensional sensing
  • (170.0110) Medical optics and biotechnology : Imaging systems

Demonstration of CW mode locked Cr:F laser using Self Shortening and Transverse mode Degeneracy driven Mode Locking

  • J George, P Thakur, K Bindra, and S M Oak
  • received 05/26/2014; accepted 10/14/2014; posted 10/15/2014; Doc. ID 212687
  • [full text: PDF (2618) KB)]
  • Abstract: This paper reports nearly Fourier transform limited CW mode locked Cr:Forsterite Laser at 1282 nm with 131 fs pulse duration based on self shortening and transverse mode degeneracy driven mode locking operating near the point of fourth order transverse mode degeneracy. The cavity employs a combination of instantaneous intensity driven self-shortening and operation on the right side of the 4th order Transverse Mode Degeneracy to generate the self amplitude modulation necessary for self-mode locking.

Keywords (OCIS):

  • (140.7090) Lasers and laser optics : Ultrafast lasers
  • (190.4420) Nonlinear optics : Nonlinear optics, transverse effects in
  • (320.2250) Ultrafast optics : Femtosecond phenomena

Measuring the correlation of two optical frequencies using four-wave mixing

  • Aravind Anthur, Regan Watts, Tam Huynh, Deepa Venkitesh, and Liam Barry
  • received 07/07/2014; accepted 10/14/2014; posted 10/14/2014; Doc. ID 215010
  • [full text: PDF (275) KB)]
  • Abstract: We use the physics of four-wave mixing to study the de-correlation of two optical frequencies as they propagate through different fiber delays. The phase noise relationship between the four-wave mixing components is used to quantify and measure the correlation between the two optical frequencies using the correlation coefficient. We show the difference in the evolution of de-correlation between frequency dependent and frequency independent components of phase noise.

Keywords (OCIS):

  • (190.0190) Nonlinear optics : Nonlinear optics
  • (190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing

Restoration of THz Continuous Wave Image obtained by Continuous Scan Mode with Large Time Constant

  • Xiao Lou, Lei Hou, Gaoyuan Guo, and Wei Shi
  • received 07/09/2014; accepted 10/13/2014; posted 10/14/2014; Doc. ID 216572
  • [full text: PDF (834) KB)]
  • Abstract: Continuous scan mode offers a relatively higher data achievement rate than the step scan mode, so it is often used in continuous wave (CW) terahertz (THz) imaging to improve the imaging efficiency. And large time constant of a lock-in amplifier provides good noise attenuation, however, it might bring motion blur to some extent in continuous scan mode. To cope with the problem, an imaging restoration method, which identifies the motion point spread function (PSF) of the motion blur, was proposed. And a modified spatial filter was used to restore the blurred image. The image quality is better than that obtained by the conventional Wiener filter evaluated by a modified no-reference motion blur metric.

Keywords (OCIS):

  • (100.2000) Image processing : Digital image processing
  • (100.3020) Image processing : Image reconstruction-restoration
  • (040.2235) Detectors : Far infrared or terahertz
  • (110.6795) Imaging systems : Terahertz imaging

Three-surface model for the ray tracing of an imaging acousto-optic tunable filter

  • Huijie Zhao, Chongchong Li, and Ying Zhang
  • received 08/14/2014; accepted 10/13/2014; posted 10/14/2014; Doc. ID 220830
  • [full text: PDF (807) KB)]
  • Abstract: A three-surface model is proposed for the ray tracing of an imaging acousto-optic tunable filter (AOTF) applied in the optical design of an AOTF imaging system. The first and the last surfaces are two refractive planes corresponding to the incident and the exit facets of the AOTF, while the property of the second surface is particularly defined to describe the change of the ray trace owing to the interaction of the acoustic and optic waves. One parameter, the acoustic angle, is firstly corrected by using the test tuning relation to compensate the nonideality of the acoustic wave. The model has been verified with a two-piezotransducer AOTF to show the usefulness. The difference between the measured diffracted angle and the modeling value is below 0.01°. The comparison demonstrates the accuracy and the efficiency of the three-surface model.

Keywords (OCIS):

  • (080.2740) Geometric optics : Geometric optical design
  • (120.4570) Instrumentation, measurement, and metrology : Optical design of instruments
  • (230.1040) Optical devices : Acousto-optical devices

Novel structured light system calibration method with optimal fringe angle

  • Beiwen Li and Song Zhang
  • received 08/13/2014; accepted 10/13/2014; posted 10/14/2014; Doc. ID 220986
  • [full text: PDF (2702) KB)]
  • Abstract: For structured light system calibration, one popular approach is to treat the projector as an inverse camera. This is usually performed by projecting horizontal and vertical sequences of patterns to establish one-to-one mapping between camera points and projector points. However, for a well-designed system, either horizontal or vertical fringe images are not sensitive to depth variation, and thus yielding inaccurate mapping. As a result, the calibration accuracy is jeopardized if a conventional calibration method is used. To address this limitation, this paper proposes a novel calibration method based on optimal fringe angle determination. Experiments demonstrate that our calibration approach can increase the measurement accuracy up to 38\% compared to the conventional calibration method with a calibration volume of 300(H) mm $\times$ 250(W) mm $\times$ 500(D) mm.

Keywords (OCIS):

  • (100.2650) Image processing : Fringe analysis
  • (120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
  • (120.5050) Instrumentation, measurement, and metrology : Phase measurement

Articles 1 to 20 of 100 Next Page >>





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings