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OPTICS EXPRESS 2013年第11期21卷 13351-13367页

作者： Lu, Jesse Vuckovic, Jelena Stanford Univ Ginzton Lab Stanford CA 94305 USA

In contrast to designing nanophotonic devices by tuning a handful of device parameters, we have developed a computational method which utilizes the full parameter space to design linear nanophotonic devices. We show that our method may indeed be capable of designing any linear nanophotonic device by demonstrating designed structures which are fully three-dimensional and multi-modal, exhibit novel functionality, have very compact footprints, exhibit high efficiency, and are manufacturable. In addition, we also demonstrate the ability to produce structures which are strongly robust to wavelength and temperature shift, as well as fabrication error. Critically, we show that our method does not require the user to be a nanophotonic expert or to perform any manual tuning. Instead, we are able to design devices solely based on the user's desired performance specification for the device. (C) 2013 Optical Society of America

关键词： computation methods Fiber optic couplers Genetic algorithms Mode conversion Optical devices Waveguide modes

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Estimation of angle-dependent mode coupling and attenuation in step-index plastic optical fibers from impulse responses

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OPTICS EXPRESS 2013年第14期21卷 17077-17088页

作者： Mundus, M. Hohl-Ebinger, J. Warta, W. Fraunhofer Inst Solar Energy Syst ISE D-79110 Freiburg Germany

We report on a method for estimation of angle-dependent mode coupling and attenuation in step-index plastic optical fibers (SI-POFs) from the shapes of impulse responses at two different fiber lengths. While alternating the fiber lengths, deviations between simulated and reference impulse responses are minimized by optimizing both mode coupling and attenuation parameters using pattern-search routines. Applying a matrix-based finite-difference approach to Gloge's time-dependent power flow equation fast computation of simulated impulse responses is enabled. We demonstrate that mode-dependent coupling and attenuation parameters converge to values that reconstruct fiber characteristics reported by other authors. We show that our results can be used for prediction of impulse responses, yielding determination of frequency responses, fiber bandwidths and coupling lengths. We conclude that our method enables characterization of SI-POFs from fiber impulse response measurements. (C) 2013 Optical Society of America

关键词： Attenuation computation methods Fiber properties Matrix methods Modal dispersion Plastic optical fibers

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Ray targeting for optimizing smooth freeform surfaces for LED non-rotational illumination

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第10期14卷 785-791页

作者： Reng-mao WU Peng LIU Ya-qin ZHANG Zhen-rong ZHENG Hai-feng LI Xu LIU State Key Laboratory of Modern Optical Instrumentations Zhejiang University

We propose an effective optimization method for generating smooth freeform surfaces for light-emitting diode(LED)non-rotational illumination based on ray *** method begins with a starting design and goes through two optimization *** initial estimate is determined using a partial differential equation(PDE)method and a variable separation *** the first optimization step the merit function is developed with ray targeting to ensure the shape of the illumination *** purpose of the second optimization is to further improve the optical performance by constructing the merit function with uniformity and *** freeform reflective and refractive surfaces,which can produce a uniform rectangular illumination without rotational symmetry,are designed using this *** results show that uniform rectangular illumination is achieved and that smooth freeform surfaces are *** ray targeting,the design efficiency can be significantly enhanced,and excellent optical performance can be achieved.

关键词： Illumination design Freeform surface Non-imaging optics computation methods

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Fast calculation of spherical computer generated hologram using spherical wave spectrum method

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OPTICS EXPRESS 2013年第1期21卷 935-948页

作者： Jackin, Boaz Jessie Yatagai, Toyohiko Utsunomiya Univ Ctr Opt Res & Educ Utsunomiya Tochigi 3218585 Japan

A fast calculation method for computer generation of spherical holograms in proposed. This method is based on wave propagation defined in spectral domain and in spherical coordinates. The spherical wave spectrum and transfer function were derived from boundary value solutions to the scalar wave equation. It is a spectral propagation formula analogous to angular spectrum formula in cartesian coordinates. A numerical method to evaluate the derived formula is suggested, which uses only N(logN)(2) operations for calculations on N sampling points. Simulation results are presented to verify the correctness of the proposed method. A spherical hologram for a spherical object was generated and reconstructed successfully using the proposed method. (C) 2013 Optical Society of America

关键词： computation methods Computer generated holograms Far field diffraction Fresnel diffraction Holographic displays Wave propagation

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Limitations of the ray mapping approach in freeform optics design

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OPTICS LETTERS 2013年第11期38卷 1945-1947页

作者： Bruneton, Adrien Baeuerle, Axel Wester, Rolf Stollenwerk, Jochen Loosen, Peter Rhein Westfal TH Aachen Chair Technol Opt Syst D-52056 Aachen Germany Fraunhofer Inst Laser Technol ILT D-52074 Aachen Germany MIT Media Lab Cambridge MA 02139 USA

It was previously demonstrated by Bauerle et al. [Opt. Express 20, 14477 (2012)] that the computation of ray paths through the optical system (ray mapping) can be used to design multisurface freeform optical elements creating a prescribed irradiance pattern for a zero-etendue source. The procedure outlined there uses the heuristic step of reducing the ray mapping's curl to improve adherence to surface integrability criteria. This Letter formally derives a quantitative estimate for the limitations of this approach in the collimated case and shows the key factors influencing the quality of the final optics. (C) 2013 Optical Society of America

关键词： Geometric optics computation methods Illumination design Nonspherical lens design Nonimaging optics

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computational and spectral studies of 1,6-dipheny1-1,3,5-hexatriene (DPH) multicomponent solutions

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SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013年 115卷 382-387页

作者： Hurjui, Ion Neamtu, Andrei Dorohoi, Dana Ortansa Gr T Popa Univ Fac Med Biophys & Med Phys Dept Iasi 700115 Romania AI I Cuza Univ Fac Phys Iasi 700506 Romania P Poni Inst Macromol Chem Iasi 700487 Romania Gr T Popa Univ Med & Pharm Ctr Study & Therapy Pain CSTD Iasi 700115 Romania

The multicomponent 1,6-dipheny1-1,3,5-hexatriene + tetrahydrofuran + water + ethanol (DPH + THF + W + E) solutions with variable content in water were studied by computational and spectral means. The computational results that indicate micelle formation in multicomponent solutions at high water content were correlated by the independence of the wavenumber in the maximum of the fluorescence on the solvent composition. (C) 2013 Elsevier B.V. All rights reserved.

关键词： DPH THF Multicomponent solutions Micelle formation computation methods Fluorescence and absorption electronic spectra

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Regression of in-water radiometric profile data

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OPTICS EXPRESS 2013年第23期21卷 27707-27733页

作者： D'Alimonte, Davide Shybanov, Eugeny B. Zibordi, Giuseppe Kajiyama, Tamito Univ Nova Lisboa Fac Ciencias & Tecnol Dept Informat Ctr Inteligencia Artificial Quinta Da Torre Caparica Portugal Ukrainian Natl Acad Sci Marine Hydrophys Inst Sevastopol Ukraine Commiss European Communities Joint Res Ctr Inst Environm & Sustainabil I-21020 Ispra Italy Univ Nova Lisboa Fac Ciencias & Tecnol Dept Informat Ctr Informat & Tecnol Informacao Quinta Da Torre Caparica Portugal

This study addresses the regression of in-water radiometric profile data with the objective of investigating solutions to minimize uncertainties of derived products like subsurface radiance and irradiance (L-u0 and E-d0) and diffuse attenuation coefficients. Analyses are conducted using radiometric profiles generated through Monte Carlo simulations and field measurements. A nonlinear NL approach is presented as an alternative to the standard linear method LN. Results indicate that the LN method, relying on log-transformed data, tends to underestimate regression results with respect to NL operating on non-transformed data. The log-transformation is thus identified as the source of biases in data products. Observed differences between LN and NL regression results for Lu0 are of the order of 1-2%, that is well below the target uncertainty for data products from in situ measurements (i.e., 5%). For Ed0, instead, differences can easily exceed 5% as a result of more pronounced light focusing and defocusing effects due to wave perturbations. This work also remarks the importance of applying the multi-cast measurement scheme as a mean to increase the precision of data products. (C) 2013 Optical Society of America

关键词： Absorption coefficient Attenuation coefficient computation methods Light focusing Radiative transfer Surface waves

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Target flux estimation by calculating intersections between neighboring conic reflector patches

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OPTICS LETTERS 2013年第23期38卷 5012-5015页

作者： Canavesi, Cristina Cassarly, William J. Rolland, Jannick P. Univ Rochester Inst Opt Rochester NY 14627 USA Synopsys Inc Wooster OH 44691 USA

We propose a fast algorithm to estimate the flux collected by conic reflector patches, based on the calculation of intersections between neighboring patches. The algorithm can be employed in conjunction with the supporting ellipsoids algorithm for freeform reflector design and is shown to be orders of magnitude faster and more scalable than the commonly used Monte Carlo ray tracing approach. (C) 2013 Optical Society of America

关键词： computation methods Illumination design Nonspherical mirror surfaces Nonimaging optics

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Design method on the stabilized zoom lens design of focal-length-variable elements

Design method on the stabilized zoom lens design of focal-le...

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International Conference on Optical Instruments and Technology - Optical Systems and Modern Optoelectronic Instruments

作者： Hao, Qun Cheng, Xuemin Du, Ke Beijing Inst Technol Sch Optoelect Beijing 100081 Peoples R China Tsinghua Univ Grad Sch Dept Precis Instrument Beijing 518055 Peoples R China

ISBN: (纸本)9780819499608

The theoretical method for analyzing the first-order optics of stabilized zoom lenses with two focal-length-variable elements is presented. The first and second derivatives and the Hessian matrix of the zoom equations with respect to the Gaussian parameters are determined to represent the sensitivity of the zoom ratio of the system to changes in the corresponding system variables. Four-group stabilized zoom lens designs with 2: 1 and 5: 1 zoom ratios are successfully investigated.

关键词： Geometric optics computation methods Lens system design

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Rapid focal shifting optics for inline 3D image capture

Rapid focal shifting optics for inline 3D image capture

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Imaging Systems and Applications, ISA 2013

作者： Gray, Dan Chen, Hongquiang Czechowski, Joseph Harding, Kevin GE Global Research One Research Circle Niskayuna NY 12309 United States

ISBN: (纸本)9781557529756

There are many visual inspection and sensing applications where both a high resolution image and a depth-map of the imaged object are desirable at high speed. Here we present a novel lens system with high-resolution and wide field-of-view for rapid 3D image capture. The design achieves this using a single lens with no moving parts. A depth-from-defocus algorithm is implemented to reconstruct 3D object point clouds and matched with a fused image to create a 3D rendered view. © OSA 2013.

关键词： Clouds computation methods Focal points Structured light Three dimensional imaging Wave plates Imaging systems (110.0110) Three-dimensional sensing (150.6910) Optical design and fabrication (220.0220)

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